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My Flats, opinions please

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8 replies to this topic

#1 inoxtrim

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Posted Yesterday, 07:48 AM

I am starting in astrophotography with DSLR NIKON 5500 camera, & Nikon backyard

celestron 102SLT AVX Mount
I have some doubts when it comes to obtaining the flats during the session.
I am using a led ligth pad, I try  center the  histrogram as much as I can , but I do not get it, I attach a file of one of my flats so you can take a look and give me your opinion. regards !!!!

 

Thanks 

 

https://drive.google...iew?usp=sharing


Edited by inoxtrim, Yesterday, 05:21 PM.


#2 Gipht

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Posted Yesterday, 10:02 AM

No picture attached.


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#3 mxpwr

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Posted Yesterday, 10:56 AM

I've had good results with using a blank A4 page at 45 degree angle towards the optical axis and have that illuminated with a light source of about 6000k (or just plain on a sunny day).
This way you have no vignetting from the light source.
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#4 inoxtrim

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Posted Yesterday, 05:21 PM

Sorry, now is attached



#5 kyle528

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Posted Yesterday, 05:41 PM

There doesn't seem to be much agreement on what a perfect flat should look like. Your attached flat looks almost exactly like the flats I end up with, and they seem to work fine. I just use a white shirt pointed at the morning sky. I don't pay much attention to the histogram on the flats (not saying this is right, but it works for me), I just let aperture priority take care of it. I've not had a problem with this process yet. 


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#6 gcardona

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Posted Yesterday, 06:21 PM

The most important thing to consider when taking flats is that you want your flats to be as bright as possible without saturating the sensor. This is why you should look at the histogram to make sure the right hand shoulder is not near the edge.


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#7 mxpwr

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Posted Today, 01:03 AM

I've noticed some luminosity gradient in the upper left corner of your flat.

At least for me, flats show fairly symmetric vignetting, and if not, I got uneven illumination, when taking the flat.
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#8 44maurer

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Posted Today, 04:08 AM

335A565F 7029 4B78 995D 2A60D5126C22

 

Something is odd with the bottom and the top of you flats.


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#9 inoxtrim

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Posted Today, 08:39 AM

In trying this time with sunlight and a white shirt and I think the result has improved a lot, what I can not get in the histrogram is to join RGB, the blue is always more to the right than the others, I do not know what to do?

Attached Thumbnails

  • Flat.jpg



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