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David Fitz-Henr
03-05-2010, 08:34 PM
I've recently acquired an STL-11000M (class 2 chip was not much more than half the price of a class 1 camera) and this is my first attempt at tri-colour imaging. The STL is intended for a larger telescope I am building, but in the meantime I have tried to use it on my 200mm scope with just a 2" Moonlite focuser and Paracorr. Unfortunately, the 2" focuser isn't really up to the weight and flexes a bit (esp near the meridian). To compensate for the weight I have rigged up an high tech adjustable anti-gravity device (see attached image) which helps keep the flexure in check.
Anyway this is a 6hr:50m (L+Ha)(R+Ha)GB image (yep - dived in boots and all). I gave substantial weight to the Ha which has given a fairly red interpretation. I'm not totally happy with the stars as I found it quite challenging to remove the halos. Anyway, got some good tips from Marcus (marc4darkskies) to get me going in photoshop, but really still a bit of a novice. The focus was a little soft as I found the Paracorr did not yield a flat field, due I think to the Paracorr / CCD distance (it seems to be more critical than the specs say). I will be doing some tests later to determine the optimal spacing.

Small image:
http://www.pbase.com/david_fitz_henry/image/122894325
Large image:
http://www.pbase.com/david_fitz_henry/image/122894325/original

Bolts_Tweed
03-05-2010, 09:02 PM
Yessssssss

Bungy imaging - thats what will spark up the hobby - extreme imaging

Nice image mate BTW - nice camera aren't they - a mate just got one .

Mark

DavidTrap
03-05-2010, 09:45 PM
Nice image.

What's the difference between a Class 1 and 2 chip (other than dollars!)?

DT

renormalised
03-05-2010, 11:55 PM
Not a bad first attempt!!!:)....

Better not let the US Government know you're playing around with this sort of thing. You'll end up kidnapped and disappearing down the black hole at Area 51 before you know it!!!!:eyepop::D:P

renormalised
04-05-2010, 12:02 AM
The number of column defects that are present in the chip....a Class 1 chip has no column defects whereas a Class 2 chip can be expected to have a few (not very many). Column defects are where you get defective pixels in the columns of pixels running down the face of the CCD chip.

spearo
04-05-2010, 01:52 AM
nice shot
and I love the anti-gravity solution!
frank

David Fitz-Henr
04-05-2010, 01:49 PM
Thanks Mark. Yes, the class 2 chipped cameras were on special (on top of already being $2K USD cheaper), so I moved the planned purchase forward in my timetable - hence the usage with a smaller than optimal focuser.





Yes, a class 2 chip can have a maximum of 2 column defects and there is also an increased tolerance on cluster defects. However, I haven't noticed any column defects in my calibrated images, and Peter Ward mentioned to me that the manufacturing appears to have improved to the point where there is not much difference. I've also read that a class 1 chip can develop column defects later anyway.




Whom do you think I stole the plans from !!??!!



Thanks Frank - It obviously takes a very sophisticated intellect to come up with something like this! Very complex - operationally (stole some elastic from my wife's sewing cabinet late one night) and technically (how long is a piece of elastic?) ...

multiweb
04-05-2010, 06:23 PM
Nice one David. Some very nice details in there. :thumbsup: I like your suspender system too.

Hagar
05-05-2010, 06:39 PM
Very nice David, I love the inovative anti gravity device. Looks a little red. Maybe a little adjustment to the colour balance needed.

Still a great first attempt.

DavidTrap
05-05-2010, 07:39 PM
Thanks for the explanation re Class 1 v 2 chips.

Are there any other warranty issues or the like?

DT

renormalised
05-05-2010, 07:59 PM
Better watch out for dark coloured, old model cars appearing in your driveway....and guys dressed in trench coats!!!!:):P:P

David Fitz-Henr
05-05-2010, 10:26 PM
Actually the old model car is mine - what do they say again when your scope is worth more than your car?


It's a standard SBIG warranty (1 year). Although it is an anti-blooming chip, it initially showed small blooming artefacts on saturated stars. I fixed this myself following SBIG's instructions (from their website) to perform the adjustment. The other issue I had was that the chamber window kept dewing up; so I returned it to Peter to service under warranty. Apparently new STL cameras now come with just 2 strip heaters on the CCD chamber as standard, whereas they used to come with 3. I would request the extra one if you are considering purchasing.


Yes, my initial step was to use DDP to stretch the Ha and Luminance images prior to PS. I gave heavy emphasis to the Ha and this has contributed to the reddened appearance of the nebula; adjusting the colour balance doesn't really seem to work here after the fact. I may go back and change the initial stretching of the Ha and blending to get a more "natural" colour and reprocess (I believe this is called "doing a Sidonio" in IIS parlance).


Merci beaucoup!

renormalised
06-05-2010, 10:53 AM
You've got your priorities right:):P