It all looks very good to me so far. Only using the new system will give a better idea of what is possible.
Finally below the white area around the Cave Neb image is the area of the PLI 16803 4096x4096 pixels with the RH200. The second image shows Rob Gendler's image superimposed on the RH200 image with Registar.
Thanks Mike. It is quite difficult to make very large bets on new 'untested by real users' equipment when neither of us gamble. It is the only vice I do not have.
I am sure the 'coma' at the corners will be minimised by quality square 50mm filters on the 36.8x36.8 mm sensor of the PLI 16803.
I did get the Astrodon Filters, LRGB and HA,OIII and SII. The NB were all 3nm.
It all looks very exciting. The thing about coma in corners is not to get too worried about it. Almost all scopes seem to have troublesome corners with the 16803. It reveals all sins. You can get the camera as square as possible and the metal back distances perfect. Then if need be you can always crop a little. The beauty of the large sensor is you can crop. You can't grow an image from a small sensor!
You'l love the PL16803. Its a fabulous camera. Still the market leader.
Greg.
Last edited by gregbradley; 05-12-2011 at 01:22 PM.
All those images present quality optics. What defects I do see are most likely the result of field rotation or stacking rotation. It makes it hard to see any coma whatsoever. I suspect you will put this altogether and have little if any trouble with its operation.
All those images present quality optics. What defects I do see are most likely the result of field rotation or stacking rotation. It makes it hard to see any coma whatsoever. I suspect you will put this altogether and have little if any trouble with its operation.
What are you doing about dew amelioration?
Paul I have a PID (proportional integral differential) pulse width modulated temperature controller I use for my Peltier Fridge. I will use this to maintain the optics temperature within about 0.2 degrees C of a set temperature and thus the dew shield at or by a lesser amount. This means focus does NOT change with ambient temperature. This worked very well with the 300mm lens and it also stops condensation on very expensive optics during periods of inactivity as I leave the heating on 24/7.
It all looks very exciting. The thing about coma in corners is not to get too worried about it. Almost all scopes seem to have troublesome corners with the 16803. It reveals all sins. You can get the camera as square as possible and the metal back distances perfect. Then if need be you can always crop a little. The beauty of the large sensor is you can crop. You can grow an image from a small sensor!
You'l love the PL16803. Its a fabulous camera. Still the market leader.
Greg.
Yes greg you are correct about cutting bits off. The RH200 should arrive before xmas but it depends on all going well with some part suppliers at the other end. I would prefer the optic delivered at top specs and not rushed.
This was a once off opportunity to really invest in top of the line equipment. I am sure I will not suffer from buyers remorse as it is now down to me to get to grips with it all.
I will admit that it was Mikes images with his system that fired up my neurons.
There's always a bum piece of equipment out there from any Manufacturer Martin. Perhaps also you were early in the development of the Proline. It matured later than the Apogee and is why I got a U16M instead of Proline originally (apart from price). U16M is a great camera but slow to cool and cooling too weak, downloads slow otherwise a great camera. STX sounds like a great camera but non sealed chamber needing desiccant is a bad weakness compared to both FLI and Apogee. Self guiding would be handy at times plus accessories eventually should be awesome. I wouldn't mind one myself especially now they have matched the price of FLI and Apogee. Proline had some issues early on in its development about 3 or 4 years ago now. They were all solved and from following the FLI group I don't see any reported regular issues. Neither does the U16M,
FLI is behind in accessories and guiding accessories like off axis guiders, AO units or some sort of self guiding solution. So is Apogee.
All of them are very heavy.U16M probably the least so it tends to have less flexure issues and that's a big plus. They all seem to be very reliable.
The bottom line is all 3 are excellent cameras. When you've got a good FLI though its hard to beat the powerful cooling, the fast downloads, an RBI system that works (not that important with 16803), sealed chamber,
low noise, no cover slip option, good shutters and antireflection coatings on CCD windows and masked, dew heaters. The main difference is perhaps convenience in use as they all do the job its just how you get there. Not so with KAF09000 chip though. No RBI annihilator and you're asking for trouble. My main complaint is lack of integration of the various FLI devices. They are all stand alone really and you end up with too many cables or use the Proline hub and perhaps get the occassional hub failures.
My main complaint is lack of integration of the various FLI devices. They are all stand alone really and you end up with too many cables or use the Proline hub and perhaps get the occassional hub failures.
Greg.
What's wrong with using the Proline hub? I run the PL16803, CFW and Atlas focuser all from the PL16803 hub so its 1 power cable to Proline and one USB to the computer - quite neat..?
I guess you have an instrument rotator and guide camera in your collection at the back of the scope too huh?
What's wrong with using the Proline hub? I run the PL16803, CFW and Atlas focuser all from the PL16803 hub so its 1 power cable to Proline and one USB to the computer - quite neat..?
I guess you have an instrument rotator and guide camera in your collection at the back of the scope too huh?
Mike
No I don't have an instrument rotator. To be fair I really have had only one trouble and that was with the ST402 in the hub. It seemed incompatible yet other times it worked. Basically unreliable. When it mucked up I would find the filter wheel would also stop being recognised. Computers recognise the hub - then - the devices in the hub. So if the hub drops out then all of the devices on it drop out.
In hindsight it really was only the ST402 for some reason. So Bert has a good plan there sticking to one manufacturer for different devices where you can so you are more likely to have them all compatible.
I have had a lot of USB hub issues in the last 2 months and bought lots of hubs and they are usually so far all trouble.
I now have a HiTec astro hub and perhaps that will work well. It gets good reviews.
True, hermetically sealed merely means airtight. Obviously there are degrees of air tightness.
The Apogee brochure page 8 says their inner chamber are sealed with Argon gas. The chamber has a lifetime guarantee against condensation.
FLI also does the same although I don't think they offer a lifetime guarantee and say you may need to purge the gas every several years.
STX sounds much the same but has a desiccant plug which perhaps works much like the lower SBIG models and requires baking from time to time.
If it doesn't and is just an added precaution and will operate like the Apogee and FLI in this regard then I stand corrected.
I am not criticising the STX as I think its an awesome camera I'm just pointing out a difference.
Either way its not a big deal but of course if you never need to bake desiccant I think thats a plus. I also wouldn't let it stop me from buying an STX as it has many awesome features the others don't and seems to have nicely closed the gap between these other makers and perhaps gone past them. The different guiding techniques, the accessories and integration, the extra channels. Now the prices have dropped its really good value.
It all looks very good to me so far. Only using the new system will give a better idea of what is possible.
Finally below the white area around the Cave Neb image is the area of the PLI 16803 4096x4096 pixels with the RH200. The second image shows Rob Gendler's image superimposed on the RH200 image with Registar.
Bert
My compliments for your new purchase Bert, I know personally the guys making these instruments and the company is very reliable.
As far as I understood from him the problems of the border were due to the wrong filters used during the preliminary tests, in fact such a fast scope need large filters and when they tested it with a 24x36 camera the 50mm round filters literally cut part of the light creating the strange shapes of the corner. So this should not be a problem with your 50mm square filters.
I am curious to see how the veloce will perform with the large 16803 chip, afaik this camera was optimized for 24x36 formats so you will push it to the edge..
As far as I understood from him the problems of the border were due to the wrong filters used during the preliminary tests, in fact such a fast scope need large filters and when they tested it with a 24x36 camera the 50mm round filters literally cut part of the light creating the strange shapes of the corner. So this should not be a problem with your 50mm square filters.
I am curious to see how the veloce will perform with the large 16803 chip, afaik this camera was optimized for 24x36 formats so you will push it to the edge..
Keep us posted with your results
Clear skies
Marco
Thanks for that information Marco. You have erased any remaining doubts I had.
Here is an image of the Lagoon and Trifid nebulae done with my Canon 5DH and 300mm F2.8L at f/3.6. 12MB
Vignetting with this system causes 50% drop in signal at left and right edges and about 65% drop in the corners. As you can see from this full frame image it is barely noticeable.
It is a problem with making seamless mosaics though and about 10% of each side needs to be cropped and about 5% top and bottom.
As I am mainly interested in making very high quality widefield mosaics the new system will cover almost as large a useable area for mosaics.
it's a little different at F6+
