Would like to get started but ...

[mikey]

I have read good things about StarTools and have downloaded a trial version. But I seem to be behind the eight ball from the start in that I do not seem to be able to properly open my calibrated files for processing.

My 64 bit PC runs Windows 7. I use an Atik mono camera which creates 16,572KB fits files. I use Atik's program Dawn to calibrate and stack the captured lights to produce an image in tif format (typically about 8,000KB in size). Tif is the only format that is output by Dawn. If I open that tif file in Photoshop I see that its mode is shown as RGB color and 8 bits/channel. But when I try to open it in StarTools I get the message “Could not read file. Make sure image is a FITS file, an uncompressed, IBM PC byte-order TIFF file or a PNG file”.

Using Photoshop to change the tif file's RGB color mode to Greyscale and/or changing the 8 bits/channel to 16 bits/channel and trying to open the saved result in StarTools only produces the same result “Could not read file ...”. Using Photoshop to save the tif file as a PNG file does allow me to open it in StarTools but I note that the PNG file size is quite a bit smaller being just over half of the tif file size. So I assume that quite a lot of data may have been lost in the conversion from tif to PNG which is not really what I want.

I am comfortable using Dawn and, as things stand, because of the matter outlined above I am doubtful that StarTools will suit my purpose but any advice will be most welcome.

[ChrisLX200]

I have read good things about StarTools and have downloaded a trial version. But I seem to be behind the eight ball from the start in that I do not seem to be able to properly open my calibrated files for processing.

My 64 bit PC runs Windows 7. I use an Atik mono camera which creates 16,572KB fits files. I use Atik's program Dawn to calibrate and stack the captured lights to produce an image in tif format (typically about 8,000KB in size). Tif is the only format that is output by Dawn. If I open that tif file in Photoshop I see that its mode is shown as RGB color and 8 bits/channel. But when I try to open it in StarTools I get the message “Could not read file. Make sure image is a FITS file, an uncompressed, IBM PC byte-order TIFF file or a PNG file”.

Using Photoshop to change the tif file's RGB color mode to Greyscale and/or changing the 8 bits/channel to 16 bits/channel and trying to open the saved result in StarTools only produces the same result “Could not read file ...”. Using Photoshop to save the tif file as a PNG file does allow me to open it in StarTools but I note that the PNG file size is quite a bit smaller being just over half of the tif file size. So I assume that quite a lot of data may have been lost in the conversion from tif to PNG which is not really what I want.

I am comfortable using Dawn and, as things stand, because of the matter outlined above I am doubtful that StarTools will suit my purpose but any advice will be most welcome.

It was probably compressed by Dawn, open it in Photoshop again and just use 'Save As' and overwrite the TIFF ensuring no compression is being used, it should then open in StarTools. I find TIFFs saved in AstroArt 5 produces the same problem.

ChrisH

[Amaranthus]

You could also try opening the TIF in Fitsworks and then re-saving as a .FIT

Then StarTools will definitely be able to open it.

[midwayexpress]

Just note to the original poster. I strongly strongly advocate against using Dawn for stacking. While I like Artemis capture a lot the problem with Dawn is that it does only process in 8 bit so you lose A LOT of quality vs. the 16 bits that your camera is imaging in. Dawn also does a poor job aligning images. I haven't posted it yet but I'm going to post a comparison of stacking programs over on Cloudynights especially for OSC users. My conclusion is that DSS (free), MaximDL (expensive), PixInsight(expensive), Nebulosity (cheap), and CCDStack (hard to use) in that order are the best options. (DSS being contingent on you using the proper settings). Anyways I would download a copy of DSS or a 30 day trial of MaximDL and give those a shot. You will get a MUCH higher quality image.

[mikey]

Guys. Thanks for your very useful replies. They are much appreciated.

ChrisH, you are quite right and I'm embarrassed that I didn't figure that out for myself.

Amaranthus, I'll definitely keep Fitsworks in mind should I need to use it.

Midwayexpress, the comments that you make are food for thought. I do like Dawn, mainly because of the very friendly user interface although it really struggles to stack if any significant field rotation is involved. But if it detracts from the captured signal then that's another matter. I've just downloaded DSS and tried it out. It seems to deliver a calibrated file size equal to the original fits lights so I guess that all captured data is preserved. It's uncomfortable moving away from one's established comfort zone but I think that you're right and that giving Dawn a miss is probably the way to go.

Mike