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Post by ChrisV on Sept 25, 2016 3:51:42 GMT
Howie has got me all excited about DSLRs. Hope I don't regret this.
In June (I think) I borrowed my son's 600D and tried a few shots through my 80mm refractor. Great, not huge in sensitivity but even with no focal reduction (F5.9) astromtery.net says I have an FOV of 2.35 x 1.57deg.
It looks like modding the camera to get rid of the IR filter is the way to go. I can't destroy my son's camera so I though I'd try and pick up something cheap that I could attack. I looked through the Gary Honis website. Is this the best website in the world or what ? Its a mine of information - the guy is a genius.
Camera #1 = 450D A few weeks later I got a 450D on IIS that was in bits with no sensor. Bought a sensor on aliexpress for $25 ... waiting ... waiting. In the meantime I put the camera back together. When the sensor arrived (2 weeks later) I did the Gary Honis mod to rip out the filter. Its easy. Stuck it in the camera and it works ! So set it up on my scope with great expectations. But I'm having problems getting it going. It turned out that one of the connectors on the camera main board is loose - so it only works intermittently. Damn. That'll take a while to fix. It can sit in a box for a while while I think how to sort it out.
Camera #2 = 550D So thought I'd try and find a cheap working camera that I could mod - if I screw it up so what. On the Honis website I used the 600D as the benchmark. Nice low noise, good QE for a dslr and get do high ISOs. The 100D is nice and light but looks very noisy, ditto the 500D. Set my sites on either an 1100D or a 550D. They are not too far off the 600D in terms of read noise, dark noise & QE, and can go up to ISO6400 which seems to be what Howie is using.
So I looked for something on ebay or gumtree for something under $100. Yes ! Found a 550D for $45 - cheap cause the autofocus doesn't work, it a bit worn looking and has no lens (but shutter count not bad). Who needs that stuff. It arrived during the week. And it works.
Testing the 550D Watched Howie's Astrotoaster youtube for the umpteenth time and finally got an hour or so between the clouds. The weather in Sydney has been crap lately. Got some pics even though the stacking looked weird all the time. So no useful 'live images' to show. Note to self about the bad stacking - you have to reset the stack on each new object. Wow, was that dumb.
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Post by ChrisV on Sept 25, 2016 4:24:48 GMT
Testing the 550D un-modded. Since my live stacking with astrotoaster was a disaster I've gone back and redone the stacking. I've put the stacked images on flickr, think I got this link right www.flickr.com/photos/142678292@N07/albums/72157673128776072. Looks like a bit of gunk somewhere and some coma. Or is that vignetting ? So next the mod to see how it compares. Just gonna pull it apart now and do the Gary Honis modification, IR filter removal. Then I'll redo these shots and see how they compare. Don't know when, today is supposed to be cloudy.
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Post by ChrisV on Sept 25, 2016 7:02:27 GMT
Filter removed, and the 550D still works. I forgot to take a before shot with the 550D. So here's a before with my phone and the after through my scope with the modded 550D The modded camera is showing those tree nice and red. So all looks good. Next up, some DSOs
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Post by davy on Sept 25, 2016 8:31:30 GMT
Looking great Chris,, yes the old DSLRs are now getting overlooked astronomy wise,,but look at the images getting produced with canon software and astrotoaster and byeos and astrotoaster..
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Post by Dragon Man on Sept 25, 2016 11:45:12 GMT
Your pics look great Chris. Yes, I can still see some noise in there. Seems more noise than I get with my 350d. And the vignetting shows up. Doesn't matter though because at that wide FOV you can crop it out and still have a fantastic image and FOV. Well done so far.
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Post by howie1 on Sept 25, 2016 21:51:12 GMT
Hi Chris ... sorry I haven't been on the forum for a while. I've been working on a presentation for the Southern Astronomy Society. While doing it I found a desktop video capture program and have been figuring out how to use it. And at the same time we had 2 nights of crystal clear skies so I went with fellow member Steve (LoganSkies) to a dark site outside Brissie to see if the vid capture app works. It did.
So ... three 20 min vids ... hd so watch in full screen and at double speed via using the YouTube viewer setting cog, so you can still hear the audio but fly through all 3 vids in about 25 minutes. Live captures of the bright stuff.
And you can see workflow and in some of the parts the settings ... but in the near future (they reckon it will be good viewing in a few days time) I will use the new desktop capture to do a tute on setting the best AT for a particular object and how to know when to use ISO6400 vs when not to etc. Basically its based on the first 'test' frames of the object which allows you to figure out both the objects brightness as well as seeing conditions. It's best explained in vid than babbling on in the forum in words! LOL
But when out there at really crystal clear dark Moonless skies I found a single 30 second ISO800 frame was good enough to use .... and with absolutely amazing results.
The 3 vids are ...
Any questions just ask away.
cheers Howie
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Post by howie1 on Sept 25, 2016 22:06:39 GMT
When you get your modded Cannon working ... if you shoot in RAW then you will have to color balance using the RGB sliders in astrotoaster or the images will look very red and tough to adjust. BUT ... I keep seeing everyone using AT using RAW cos they figure it has the best quality and it is what is used in astrophotography ... but you really do NOT have to do that. Especially for EAA! We are trying to do something diff to AP and yet they keep using RAW almost like its a law! LOL.
But, we're not trying to get AP quality ... we want good quality but in much shorter and with mush less hassle. All mine are jpeg, small but fine quality setting. You will see the EOS Util window in my vids showing the S1 (small setting symbol) with the smooth (fine) arc figure beside it. If you know what I mean.
Anyway ... if you use Jpeg small but fine, and then at midday do a custom white balance by shooting a grey scale card ... or dark bitumen road surface ... then it will color balance for you so the camera will be close to perfect WB for shooting night objects AND still let the IR through because the sensor is still getting all the goodness of that IR hitting the sensor. You will see this in the vids ... the AT RGB sliders are all at dflt settings yet the colors of stars and of nebulosity are perfect! That's one less thing to have to worry about! If I shot in RAW it is very debatable whether I'd get any benefit out of them being RAW given they are single 30 sec shots. But to get decent color balance and stretches with RAW it is so different I would have to spend at least 10 minutes moving sliders and RGB and diff stretches and so on to get a decent RAW image. I am sure you've seen the NSN broadcats where you see them go 60, 90 or 180 sec and stack heaps on just globulars!! They move all the sliders and stuff to finally after 10 mins get a decent image. That's the hassle with RAW. Shoot jpeg and it is very easy. Once you find the ISO and secs exposure for your first object of the night, you can slew to all objects leaving the settings pretty much alone and every object you go to will be pretty close to perfect on the first frame!
Anyway ... few days time its supposed to be clear and I will get out and make a vid on exactly how to process by picking one target and shoot various ISO's and so on and so forth.
cheers
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Post by ChrisV on Sept 25, 2016 22:56:19 GMT
Thanks all.
Had a go with the modded camera last night. I'm sure it was better. But clouds kept rolling through so it mucked up my live stacking - only got about 2/10 decent subs. So don't have anything to show. Will have to figure out how to reject those on the fly. And will stack the OK ones tonight to show. Must read instruction and watch you new vid Howie !!
I've been using jpgeg S2 in case i want to blow up to see smaller things while stacking ?
And I get what you mean about the red. Red, red everywhere. At first i thought it was thin clouds or mist as it was very dewy last night. It made it very hard to stretch in astrotoaster. But some single 30s subs looked okay when stretched in fitswerk.
Also not used to the weightier camera. Just before I gave up I noticed later that it was going out of focus. Oops the camera had slid out a bit. Hmmm.
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Post by ChrisV on Sept 26, 2016 11:55:28 GMT
Helix Nebula. Both ISO6400 and cropped 550D before modification. Stack of 11x 30sec subs After modification. Stack of 12x 20sec subs
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Post by ChrisV on Sept 26, 2016 12:00:07 GMT
And Lagoon Nebula. ISO6400. 13x 20sec subs before modification 12x 20sec subs after modification
I'll put these up on flckr later as they are very compressed and don't look good.
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Post by Dragon Man on Sept 26, 2016 12:15:50 GMT
Fantastic examples of the Mod!
The difference is amazing.
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Post by ChrisV on Sept 26, 2016 13:31:49 GMT
Ken Yes it kind of blew me away. And seeing much worse on the night with the modded camera. You don't even need to stack if you can cop a little noise. Small wonder you lose some much red/IR. The filter I took out is blue, so it must savage that DSO light !!! The next morning I thought I should take a pic - but couldn't find it - rummaged through the bin to find the pieces but didn't want to go too deep. I think I can almost see an end to this rain. Cheers, Chris PS - link to the stacked images www.flickr.com/photos/142678292@N07/albums/72157674315912666/with/29858917921/
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Post by davy on Sept 26, 2016 14:26:24 GMT
Right Chris, no more nmdded DSLR stuff,,,I can feel my wallet groaning,lol 😂
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Post by howie1 on Sept 26, 2016 19:27:16 GMT
Great images Chris ... but you should do the daytime white balance like I said. Saves heaps of grief in trying to get color right.
The principle in "normal" photography is to take a test shot in bright daylight with a person holding a digital greyscale card vertically in front of them. Then they put it down and you take the shot of them posing or whatever. Then later in photoshop/lightroom/canon digital photo professional/etc there is an auto white balance "eye-dropper" tool which you drag and drop onto the image of the greyscale card which they were holding in the test photo. That automatically sets the correct white balance for the images shot. But there's another way to do it which is what we need to do!
You set the camera to do that white balance "correction" internally. You set full auto and take an image of a digital greyscale card so the grey fills the entire photo FOV - the shot taken is just all-over grey. Then using the camera menu you navigate to Custom White Balance, and it will ask you to choose a photo. It will be the last image shot ... which of course was the complete FOV greyscale image you took. So select that and that's that. The camera lcd will display a Custom white balance symbol - two small triangles on either side of a small black rectangle. Your shots with the modded camera will be white balanced. But what if you don't have a digital greyscale card?
If you don't have a digital greyscale card, go out in bright midday daylight and shoot where the bitumen road is in shadow. Its got to be bright sunshine but the bitumen in shadow. Stand in the shade over the top of the shadowed bitumen area and point the camera down and fill the image FOV with the in-the-shadow-bitumen. Select that for the greyscale image when you use the menu to set Custom White Balance with that grey full FOV bitumen image. If the camera won't come to focus set manual focus.
Once set, all jpeg shots will auto white balance using that. A test shot in daylight will produce a strange almost monochrome image with tree's a wierd ghostly light grey etc (in full modded cameras, but slightly different in half spectrum mods). Whatever it looks like, so long as you followed the procedure it will be correctly white balanced for jpegs to come out fullly correctly white balanced! I mean at night DSO's, star colors etc will all "look right!". Except if you shoot in RAW.
RAW shots will still appear totally wrong and red, even though using that custom white balance. BUT ... along with every RAW image shot is all the metadata information which processing software like Canon's digital camera professional/photoshop/lightroom/etc. In that metadata is ... the new corrected white balance! Those programs "read" the white balance metadata information and use it when you use the whitebalance correction tool "eyedropper". Unfortunately AstroToaster cannot do this and the images are still way too red. You will have to adjust manually and it wastes a bunch of time. IMO. Having said that, I know AT uses the DSS settings, and in DSS under the RAW setting tab, or somewhere in DSS, there are debayer and other type of processing settings and maybe, just maybe, there is something in there you can set so when you tell AT to read the DSS settings, it might actually work and auto color balance the RAW custom white balanced shots too.
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Post by howie1 on Sept 26, 2016 20:10:49 GMT
Next S2 vs S1 ... and your choice of S2 so you can "blow things up to see smaller things" ...
Ummmm ... on my 650d, S1 is 2592x1728, and S2 is less "quality" at 1920x1080. I get less "sharpness" if I set S2 compared to S1 to be able to zoom in and see finer detail. Or are you saying the image scale FOV at S2 is more "zoomed" for you right from the get go / more magnified astro FOV? In which case I need to try that out! I didn't think so because I have shot at RAW which is full 5184x3456 pixels and the objects FOV is the same as when I shoot at S1.
When you set S1 S2 etc in the camera menu, as you use the arrow button to move through each setting it displays the X and Y pixels on the LCD as you toggle through each setting.
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Post by howie1 on Sept 26, 2016 20:39:39 GMT
davy,
I picked up my full spectrum modded Canon 650d for $500. It also included an 18mm to 135mm lens (by itself around $400 here in Oz) fitted with a Hoya UV filter ($90 Aussie). It also came with two official Canon branded batteries, as well as a 12V cigarette adapter (to run the camera off the mounts 12V battery).
So hunt through the astromart/cloudy-nights/ice-in-space second hand forums and you can pick them up pretty cheap as folk "upgrade" or get out of the hobby. Brand new fully modded the cost a lot!
Mine aren't cooled, but as you can see from my images and those video's ... it most certainly isn't noisy. My ASI224 and old Mallincam are heaps noisier and have more hot pixels. And I've yet to try it this coming hot Aussie summer, but I saw a guy who hot glued some velcro on his OTA around the focuser, and onto the side of some small injury/freezer packs from the chemist. He'd stick one onto the velcro with the flat cold side wrapped around the base of the focuser. The cold runs up thru the metal focuser and over the 2" nosepiece/adapter to chill the camera sensor area a bit. He reckoned it worked a treat to keep the camera cool. I wonder about dew forming on the sensor ... but hey it's worth a try. The Astrotoaster website has a small lunch zip insulated bag filled with ice as the cooler. Or was that Gary Honis website? I saw a forum where a guy bought a cheap PC magnetic bearing fan and a vaccuum cleaner hose and filled an esky full of ice and the fan blew the cold air up through the vaccuum cleaner hose to the camera. Need to try that too!
cheers
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Post by ChrisV on Sept 26, 2016 22:08:01 GMT
Each in turn. Okay think i get it about the awb.
And they just retarred our street so nice and clean and black.
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Post by ChrisV on Sept 26, 2016 22:09:41 GMT
I just assumed s2 would be better but now i actually look at the pixel counts. Get what you mean.
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Post by ChrisV on Sept 26, 2016 22:24:15 GMT
I'm am avid watcher of the IIS classifieds. Saw you picking up a camera. And yes some great bargains come up now and then.
I was to impatient to wait and didn't have the $$ right now. So looked through the Honis website for the next best thing. And the 550 came up on gumtree and was close by.
The only thing that is hard is lining up objects. On my 224 I'd turn the gain up full with short exposures (<1-2sec) in sharpcap and Centre the object. On the 550 live view is a bit dim for that. Just have to be more patient.
Ii will be interesting to see how the noise pans out with summer coming. Yours will be worse than mine ! If it gets bad i can see a cooling project happening.
I just ordered a dummy battery and dc-dc voltage converter on ebay so i can run the camera off the 12V that supplies my mount.
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Post by howie1 on Sept 27, 2016 0:24:08 GMT
Aha ... dont use liveview ... the process is exactly the same as with the ZWO Chris ...
1. Scope is on its way slewing to your target 2. While it is slewing, in AT you press "STOP", "FILE LIST" and in there click "UNCHECK ALL". 3. Now click "MONITOR", "SINGLE" then "REFRESH" AT is now setup to accept and display a single frame. 4. While it is still slewing, in BYEOS or EOSUtils you click ISO to max (mine is 12,800) and SHUTTER to 4 seconds 5. When it beeps at the finish of slewing you simply click off a single 4 sec shot 6. You frame and center using that 4 sec shot. Who cares about noise and specs and stuff ... its for framing and centering the shot! 7. When its centered, change the cam back to ISO of your preference and shutter speed of your preference.
Couple of tips ... 1. ISO steps and exp times work like this (not exactly but a pretty good approximation) ... 30sec @ iso800 is same brightness of photo as 15sec @ iso1600 is same as 8sec @ iso3200 is same as 4sec @ iso6400 is same as 2sec @ iso12,800 Just replace those numbers with your scope / dslr combination. IE you may find your best results are 30sec @ iso3200, so you just change the scale to look like this ... 30sec @iso3200 same as 15sec @iso6400 same as 8sec @iso12,800 same as 4sec @iso25,200
2. There's a few faint nebs or galaxies tough to 'see' even at iso12,800 when you view the AT window, BUT theres a negative checkbox and a logarithm checkbox in the color adjustments window ... logarithm does a luminance stretch immediately brightening all the faint stuff leaving the dark stuff still dark. The faint stuff then stands out more. And if you still cannot see it, then click the negative checkbox and you'll see the inverted black dots and mist on a pure white background ... even easier to see faint nebs and galaxies and stars.
cheers
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