Converting from Raw to TIFF

[Mike Bradley]

I am using Canons Digital Photo Professional to convert my RAW DSO images to TIFF for processing in Deep Sky Stacker and Photoshop CS2. The camera is a 60D modified for Halpha. I am curious as to what settings to make in the DPP Tool Palette, especially whether to check the "Linear" box or not? How are others using this tool?

Thanks

Michael

 

 

[astroman133]

BYE Premium Edition allows you to save your images as TIFF at capture time.

[dts350z]

There is a beta version of DSS that (properly) accepts canon cr2 raw files

 

Latest DSLRs support (DeepSkyStacker 3.3.4)
If your DSLR is not supported by the current version, you can download the latest version from the Yahoo Group Link page here
Or directly here.

The list of the DSLRs supported by the latest version is available on the dcraw web site.

[Mike Bradley]

Thanks for the tips folks, I plan to try both options. I did download the latest version of BYE.

 

I am still wondering about whether or not to set the Linear checkbox in DPP though. I haven't seen any consistent recommendation in the various online sources and books I've looked at. Experience of other DPP/Photoshop users could be very helpful.

Michael

[astroman133]

Michael,

 

In my experience, linear is akin to unstretched.  If you typically use levels and curves in PS to stretch your image then I would leave the TIFF data as linear when using DPP to convert to TIFF, since it may apply some kind of default stretch if you don't.

 

That is just a guess on my part and your plan to "try both options" is a good one.

[s3igell]

I am still wondering about whether or not to set the Linear checkbox in DPP though. I haven't seen any consistent recommendation in the various online sources and books I've looked at. Experience of other DPP/Photoshop users could be very helpful.

The DPP "Linear" selection would depend on what you intended to do next with your AP Image.

 

If you were going to move straight to PhotoShop or some other "regular" Image Processing App, then you would NOT want "Linear" TIFF Data - instead you would want DPP to perform its basic Exposure / Contrast Stretching and to apply a Saturation Curve (and White Balance per the In-Camera Default or your predefined Custom White Balance).  All of these actions are the same ones which the DSLR Processor does to produce the JPG Image (if you select JPG as your Camera's Output format).

 

On the other hand, if you were going to move the TIFF file into an Astro Image Processing App (DSS, PixInsight, ImagesPlus, StarTools, Nebulosity, etc), then you want "Linear" data for use with the Calibration and Stacking and Gradient Removal processes.  After those are performed upon the Linear data (and in the case of some Apps even additional tools), then the resulting data can be Stretched and Saturated and further Noise Reduced and Sharpened.

[s3igell]

I am using Canons Digital Photo Professional to convert my RAW DSO images to TIFF for processing in Deep Sky Stacker and Photoshop CS2. The camera is a 60D modified for Halpha.

There is a beta version of DSS that (properly) accepts canon cr2 raw files.

Thanks for the tips folks, I plan to try both options. I did download the latest version of BYE.

The latest Release of DSS v3.3.4 fully supports the 60D "flavor" of CR2 file.  (I use DSS v3.3.4 all the time with the CR2 RAW Files straight from my 60D - no need for any DPP or ACR Conversion to TIFF.)

 

In general, most every updated Canon DSLR uses a slightly different "flavor" of the general CR2 File Format.  And it is then up to the few Coders who decode that latest "flavor" and make updates to their CR2 Decoding Apps - such as DCRAW (which DSS is dependent upon) - and include that code in a new Release of their Library / App.  And only then can end-user Apps such as DSS (or Adobe ACR / Lightroom) produce updates to their Apps which integrate support for that newest DSLR's CR2 Output.