Metering Mode in DSLR's for taking FLATS...?

[Scott Kuchma]

I'm just wondering if there is a recommended Metering Mode to use on a DSLR when taking FLATS ?On my Canon I have the choice of Evaluative , Center-Weighted , Spot and Partial . Since the FLATS will show up the vignetting in the Optical path of our Scopes , with varying brightness around the edge compared to the middle , I'm thinking Spot Metering may not be the best although I do use it when Imaging .

Thoughts ?

Scott..............

[wols...@gmail.com]

Scott,

You want to use the same ISO and exposure for all of your FLAT frames for an individual session so be careful using any autoexposure modes.  I shoot my FLATs using MANUAL mode.  Actually my Nikon D5300 does not recognize my telescope as being a valid lens so I am forced to use manual.

 I shoot my FLATs the next morning, I always try to evaluate a single FLAT frame using the CaLIGHTs create master feature just to ensure no saturation and good  RGB balance before I dismantle anything.  

The Center-Weighted option would be my choice but I never use an autoexposure mode when taking FLATs.

Peter

[Scott Kuchma]

Hi Peter ,

I had been using the Av Mode , as suggested somewhere , but when I wasn't getting a fast enough Shutter Speed I had switched to Manual for FLATS just like for my Lights . I think I was confused , nothing new , as the Exposure Metering Options are still valid and changeable even when I'm in Manual Mode . Looking at some new Data online I don't think the Metering Mode can be used in Manual Mode as both the Shutter Speed and ISO are preset . Maybe a bit of an oversight on Canon's part still including this Option while in full Manual Mode . Interesting . One less thing to worry about eh ?

Scott................