CCD pros and cons?
Posted 14 December 2013 - 11:53 PM
Been on the DSLR site for a few years. Wouldn't say I have very good processing skills, but am very comfortable capturing.
Anyway, thinking of switching to CCD in 2014. Everyone I know uses DSLR, and I hear CCD captures data quicker. But I have a few questions first.
1. Advantages/disadvantages of One Shot Color vs Filters. Not keen on shooting the same target & switching filters several times.
2. Do they suck a lot of power? Perhaps as much as a 8-inch dew strap?
3. Are one-shot color CCD's more user friendly? That would be my guess.
4. Is processing CCD images more tricky than DSLR? Or just different? Perhaps very similar?
5. What is a price-range on a mid-grade CCD? Especially one that is more intuitive for the non-tech-savvy.
6. For framing, focus and rotation, can you get a live-view through a lap-top, like a DSLR?
And any other advice would be appreciated.
Posted 17 December 2013 - 01:54 AM
Posted 17 December 2013 - 09:46 AM
1. The OSC v. Mono debate has been had. Like Rick said, plenty of info in the archives.
2. Power? Haven't noticed. But with good cooling they will draw more than your dslr
3. In my experience there's no such thing as a CCD that is or is not user friendly. It's the software that you interact with, not the CCD. There will be a learning curve.
4. Not different at all (easier IMO because accurate calibration is easier with regulated cooling as I mentioned)
5. Prepare yourself to spend about $1200-1500 if you buy new. People seem to like QHY cameras, and they are less $$ than most. There's an older model QHY8* on astromart right now for $880 (not sure what the difference is between that and the new model)
6. Yes (again, it's all down to the software package you use... not the ccd).
*This sensor has 7.8 micron pixels. A very popular sensor right now is the KAF-8300 (lots of companies use it). It uses 5.4 micron pixels (the QHY9 uses this). You should figure out what your image scale will be with your scope(s) with both of those pixel sizes. You will want a pixel scale of less than 2 arc-seconds per pixel (better to have something like 1"/pixel so if you want you can 2x2 bin to get higher SNR for lower spatial resolution, but if you star off at 2" per pixel at 1x1 binning, at 2x2 you probably won't like what your stars look like).
Posted 17 December 2013 - 12:53 PM
I have a QHY8L and use Nebulosity 3 to take my pictures and do the stacking and preprocessing. It's fairly easy to use. Most capture software has a focus mode. Both focus mode and while capturing the software will display the previous captured frame. Although it's not a true live view, when you have short capture times like for focusing, it effectively becomes a live view. There is a nice review and demo of Nebulosity here. Which capture software you use is more of a personal preference. One noteworthy word, most OSC cameras will return Black & White images when you bin them at anything greater than 1x1 (2x2, 3x3, 4x4).
That same QHY8 is on CN in the classifies section.
Posted 17 December 2013 - 06:56 PM
Given me much info to chew on.
I must say, I'm impressed with the detail of the pics I see on this site. I suppose those who chose to buy a dedicated astro camera are less likely to be casual about their hobby.
Again, you guys have been very helpful, but the term OSC went over my head. Not exactly a wizard about this stuff. Binning is another thing I need to learn about.
Posted 17 December 2013 - 09:57 PM
Posted 18 December 2013 - 07:45 AM
There is very much a personal choice element to this so there is no absolute right or wrong answer, just what is right for you given your equipment, skies, interests, priorities, and expectations.
Posted 18 December 2013 - 09:31 PM
Maybe 2014 will be the year I finally take the leap for the best pics I can make?
Will be thinking hard about it. No rush decisions.
Posted 18 December 2013 - 09:36 PM
I suppose you could buy an older modded DSLR for $4-600. Or a new one, then get it modded for a total of about $12-1500.
It looks to me that if someone wanted a really good modded DSLR, a dedicated cam is going to be in the same neighbourhood.
Much to think about.
Posted 18 December 2013 - 11:38 PM
The way I look at it, is like this. A dslr is a general purpose photography device, that can be used for astro photos. A monochrome ccd with filters, is a general purpose astronomy device, that can be used for astrophotos, and a whole lot more (photometry, astrometry as a couple examples). The dslr is a many trick pony, as is the monochrome ccd. The two overlap in one spot only, and that's doing a 'pretty picture' astrophoto, but each can be used for many other things as well. The color astro ccd, is a hybrid device, and truely a one trick pony, covering only that trick that is the overlap between the mono ccd and dslr, altho it does that single trick, rgb imaging, better. It fails miserably at pretty much all the other tricks.
We have never regretted the upspend to dedicated ccd cameras, and will upgrade our cameras after the observatory is built in our new home. But if for no other reason, the ability to do narrow band during the full moon part of the cycle, means we wont even consider one shot color.
Then again, we do things a little different than most. As an example, instead of RGB filters, we have BVR photometric filters. They are completely useable for RGB imaging, but, also the correct filters for photmetric observations. It goes back to the difference between a general purpose astronomy tool, vs a one trick pony. BVR is only a small difference from the RGB, but become a 'many tricks' pony, whereas a set of RGB filters is a one trick pony.
Posted 19 December 2013 - 02:33 AM
2. Different for every camera
3. Not really
4. Takes longer for mono camera but results are always (much) better
6. Live view is not recommended for framing or focusing on DSLR either, use Bahtinov mask for focusing and some imaging software for framing