Morning all Gerhard addressed the following comments to me: >Greg >- 640 x 427 pixels could then be the standard to set the camera to ? >- .png format the standard ? >- for your work will do at max telephoto. >- will do stacking for party pictures. >- on a alt/az tracker do you not think this >http://shop.technopro.co.za/acuter-allinone-camera-spotter-telescope-mount-p-916.html >will be a excellent gift to the wife? Your opinion will be apreciated or >are there simpler stuff on the market ? your opinion please. Sorry for the delay in replying - I observed last night till 1am and am now busy processing the results. I just happened to use 640 x 427 -- all I did was reduce the size of your original image of 1600 x 1067 to 640 x "something" and maintaining the aspect ratio ,so it ended as 640 x 427 pixels so there is nothing "magic about the numbers used. I was a little surprised that it didnt come out 640 x 480 so it looks like your camera has its own format size. Anyway , for the present, I would not say its necessary to reduce your image size- although it will save you storage space. Scott also has a large image format from his CCD camera and 2x bins it which reduces the size by a factor of 2 and 4x (?) smaller in file size ( I think:-)). Re using PNG - a similar type of answer - PIXY -which was the program I did the astrometry on your image, either wants a FIT or a PNG file- it was easy enough to convert your image to PNG format. I think PNG is actually superior to a JPEG image (in theory) since JPEG uses compression - whether the difference is significant in your case I dont know -- I wouldnt think there would really be much difference. Yes I would prefer you use a longer focal length-especially for the high altitude stuff. Okay on your "party pictures" :-)) I had at look at the "Acuter All in One camera/spotter and telescope mount". I have not seen this before and know ZERO about it. I went to the SKYWATCHER site and this didnt give much more info - Ill do a search on the Internet and see if the manual can be located. It LOOKS useful but thats all I can say at this stage so hang onto your R3000 a bit longer and tell your wife she will have to wait -- do you think I really believe its for your wife ? :-))) -- I must try that argument on my wife! Scott suggested the "cube" - this also looks nice but I think is quite a lot more expensive than the one you mention - I think its around $600 - I have seen it advertised here in South Africa. Again I have NO real knowlegde of it - I seem to recall there was some disagreeable "flop" in it but I am open to correction. Re dead pixels - there is software available to map these pixels and remove them from the image, however I would not bother with this. If we eventually use APEX for your reductions APEX takes care of the problem internally so there is no need for flat fields, dark frames, dead pixel mapping etc- not even necessary to do any image processing at all as APEX does it all . Okay back to measuring Cheers Greg ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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