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Wanted: Celestron Nightscape 8300 CCD camera to replace a faulty unit.
A few months back, i bought my first mono camera, an Atik 383l+ from Martin @Xsubmariner off here. I hadn't had a chance to give it a whirl until last night.
I thought about getting the 80ED out, but i've been wanting to do some widefield stuff for a while, so i attached an old Tamron 135mm F2.8 vintage M42 lens i picked up last year for next to nothing. The lens needs to be stopped down to F5.6 (perhaps less, i haven't tested though) to produce acceptable stars in broadband, but i was hoping it could be used more wide open for Narrowband. I used step-down rings screwed on to the end of the lens hood to bring the aperture down to 37mm, which is about F3.65 (i did briefly try it wide open in Ha, and it wasn't that bad tbh, but i could still make out some comet-shaped stars in a few places so i opted to stop it down a bit to play it safe). I have a TS Optics filter drawer in the optical train, so i can still swap out filters without too much fuss. I still have about 3-4mm of extra backfocus space to spare, but i can already find focus as it is, so i'm not sure if it's that important that i haven't fully used it all up.
Focusing was tough. I was focusing using a Bahtinov mask on Deneb, and i had to use 10s subs (subframes) at 2x2 bin to get bright enough spikes for Bahtinov Grabber to pick up to the spikes ok. Even then, it was showing the focus error moving about quite a bit, even without me touching the focus ring. In the end i just got it as close as i could and went with it.
Conditions were not great. Some clear spells, but there was a lot of cloud passing through. I figures it would be good enough for a test session. The Phd guide graph looked horrific, and was somewhere in the 1-2" range (image scale is 8.4" so not a big deal hopefully). I bodged together a couple of old dovetails to add enough weight to counter-balance the 5Kg counterweight. It just about does. It's not perfect by any means, but hopefully sufficient for this purpose.
I would ideally like to shoot 1200s subs, but couldn't last night due to the constant clouds (Phd lost the guide star countless times). I was about to give up, but persisted and aimed for 600s subs. Glad i did, as i ended up with 6 useable subs, even if a couple were affected by some thin cloud.
Did a quick stack in APP and a 10 min process in PS, just to get a rough idea of what i can expect from this. I used Flats and a couple of Darks just to do a rough calibration. Didn't do any gradient reduction, was in too much of a hurry after packing up last night. Overall i'm fairly pleased with how it performed. I'm obviously not aiming for Samyang 135mm F2 levels of performance here, but for purely NB bi-colour mosaics i think it can do a job.
I've included a picture of the rig below as well, in case anyone's interested.
6 x 600s (1 Hr)
Atik 383l+ 2" Baader Ha 7nm
Tamron Adaptall2 135mm F2.8 (@F3.65)
I recently scored a great deal on facebook marketplace and bought Skywatcher Skymax 180 mm Maksutov-Cassegrain Telescope (f/15) with EQ6R-pro mount. I understand that long focal length telescopes are more suitable for planetary imaging. However, as I am tight on budget, I would like to use the same scope for deep-sky astrophotography. I have Canon Rebel T5 DSLR camera that I am using for taking images. Without autoguiding and a decent polar alignment, I can get ~30 seconds long shots without any star trailing, but that's not sufficient for imaging objects like M51. I would like to be able to integrate longer, say few minutes, thus would like to purchase an autoguider. Here are some specific questions I have.
1). The telescope comes with an 8 x 50 straight-through finder. If I were to use it as a guidescope, what type of image integration time can I expect? Has anyone done autoguiding for f/15 scope with an 8x50 or other finderscopes?
2). If the integration time will be an issue with the 8x50 finder scope, I am open to purchasing an off-axis-guider. However, considering the narrow field-of-view of Mak-180 telescope, I am concerned about not having enough photons from guidestar for autoguiding. For instance, with my DSLR camera, I need to integrate 20-30 seconds to see the nearby stars in M51. What type of OAG and camera would I need to autoguide with my scope? Are there affordable cameras (~$200) that would do the job for me? Would ASI120MM Mini Monochrome (~$150) do the job? What about OAG?
I plan to use phd2 software for autoguiding rather than relying on the build-in guide port on the mount. Instead of integrating for hours, I am planning to do DSS stacking of few mintues long multiple shots, hopefully this will put less strict requirements on the autoguider.
In case this information is relevant: with my current setup, I have no issue pointing my scope to a desired deep-sky object, track the object within the field-of-view of my DSLR camera for hours using the mechnical tracking of the EQ6 mount. For instance following is a single raw image of Ring nebula taken with 30 seconds shot. But it is not enough for generating high-quality images.
Thank you in advance for your help.
I'm selling a 1 year old Moravian G3-16200M Mark II camera. Please note this is the newer Mark II camera with faster downloads (on my NUC computer it was 9s.). Everything is in like new condition.
The Moravian G3-16200M MKII has a class 2 chip and the standard cooling. The camera cames with an M48 nose piece (unused), power supply with both USA and European plug, 10ft USB cable and hard case. There is also a 17mm extension that can be used if you purchase separately the larger M68 adapter. There are currently 2 read out lines that completely disappear with active cooling and proper image calibration, as is typical with a class 2 sensor.
£2240 PLUS SHIPPING, no fee for paypal. NOTE: ships from USA.
I recently upgraded to a purpose made astro-camera (Atik Horizon Color). The learning curve has definitely been noticeable, but I cant figure a couple things out. For some reason the pictures are grey scale when using N.I.N.A. I have tried different binning and formats, but the image is always black and white.
If I use the ATIK software (Infinity,Dusk) there is an option for 'Color Binning', and that seems to have fixed it for those programs, but N.I.N.A doesn't seem to have that option (you can not select anything for binning, or select 1x1, 2x2 ect.). But what makes it weirder is that the preview is always color using N.I.N.A. I used a pinhole lens cover to take pictures of my computer screen and it always shows up as color images. However, if I take that exact image file that previews in color and move it to pixinsight, it is grey-scale.
Is this a binning thing, file format problem? At this point I am just confused, if the preview of the image is color shouldn't the image data be color as well?
So far all the problems I have had with this camera have just been simple things that were new to me, but this one is really throwing me for a loop. Thanks for any help.
I've attached a couple images. The first you can see the NINA preview is color, as well with the couple other I took in the bottom right. And the other in a photo of trying to color saturate the stretched image in Pixinsight, and it says that it cannot saturate a grey-scale image. I have tried this with Tif, Fits, and various binning types.