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Another FD 03-26

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#1 MAURITS

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Posted 26 March 2020 - 10:32 AM

Again this morning a short imaging session.

Seeing was fair but I can't make a "flat frame" with a cereal diffuser bag before my Lunt front filter (I am unable to do that).

 

So this is again a image without a flat frame and with uneven illumination.

DS Lunt LS 60F/ 35F

Camera ASI 120 MM-S

 

10_29_34  Color.jpg

 

 

This is my flat taken with the cereal diffuser bag.

 

test.jpg

 

Here I have placed the same image but with only a minimun processing in PS.

 

10_29_34 Color 2.jpg

 

 

 

 


Edited by MAURITS, 26 March 2020 - 10:47 AM.

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#2 RickV

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Posted 26 March 2020 - 11:56 AM

Hi Maurits,

 

RE: but I can't make a "flat frame" with a cereal diffuser bag before my Lunt front filter (I am unable to do that).

Me too... just doesn't seem to work for me... same with out-of-focus.

 

I do my flat calibration using my captured image.

In Photoshop...

 

1 Adjust Levels to black point is above zero and bright point is below say about 240.

2 Duplicate Layer

3 Filter Dust & scratches at 68

4 Layer (subtract)

5 Image / adjustments / curves / preset / Darker RGB

5 Set Layer opacity to 50%

6 Flatten image

 

I will repeat steps 1-6 at least twice, sometimes three times.  (I made steps 2 through 6 an Action).

The end result is an gradient-free image.

 

Give it a try on your grey scale image.  I then sharpen and other things before I finally colorize.

 

This process always works for me.

 

Best,

Rick


Edited by RickV, 26 March 2020 - 12:05 PM.

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#3 MAURITS

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Posted 26 March 2020 - 01:27 PM

Thanks Rick for this information


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#4 MalVeauX

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Posted 27 March 2020 - 09:01 AM

Looks good Maurits!

 

How close to the scope is your cereal bag being placed? It needs to be a few inches out in front, not directly onto the opening into your OTA. Can you show a picture of how you place it?

 

Very best,



#5 MAURITS

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Posted 27 March 2020 - 12:09 PM

Looks good Maurits!

 

How close to the scope is your cereal bag being placed? It needs to be a few inches out in front, not directly onto the opening into your OTA. Can you show a picture of how you place it?

 

Very best,

Marty this is the cereal bag on the front filter.

 

klein.jpg



#6 MAURITS

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Posted 28 March 2020 - 04:43 AM

The flat frame problem is solved.

The cereal bag was too transparent, so I put some other above and the flat frame was perfect.

 

klein.jpg


Edited by MAURITS, 28 March 2020 - 04:51 AM.

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#7 hopskipson

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Posted 28 March 2020 - 09:08 AM

The flat frame problem is solved.

The cereal bag was too transparent, so I put some other above and the flat frame was perfect.

 

attachicon.gifklein.jpg

So you double bagged it or you used a different opacity bag?


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#8 MAURITS

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Posted 28 March 2020 - 03:09 PM

So you double bagged it or you used a different opacity bag?

Double bagged smile.gif




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