Blink comparometer

[Swagman105]

Does anyone know if a blink comparator can be obtained anywhere.
The original BCs were a mechanical photographic Image flipping mechanism Used to compare two images of the same patch of sky for differences.
I wonder if there is now a modern equivalent using software to compare digital images.

[bojan]

You can compile gif file from individual images.. Effect is the same.

[sunslayr]

I think I know what you mean, it's a little difficult to find a program that can handle fits and other raw files. I use ASTAP (http://www.hnsky.org/astap.htm), it has a thumbnail viewer and the ability to blink multiple images. Just open the stack menu, select your images and finally click unaligned blink button (>>).

[Merlin66]

Geoff,
Funny you mention blink comparators... I built one back in the 80's to compare the ASV Photographic Section images.

I just stripped and dumped it a couple of years ago....never being used with digital cameras.
Nowadays if I want to compare either images or images to star maps I use Cartes du Ciel.
To register the image to the star map, the image needs to be a solved fits file. I use Astroart to solve the image and then open in CdC.
You can use the online astrometry.net to solve almost any image.
If it's just image to image comparison Astroart can do that.

[lazjen]

If you've got PixInsight, there's a Blink process in there for just this purpose. Easy to flick through or animate to see things.

[PeterM]

Hi Geoff,

For many years now the BOSS team (Backyard Observatory Supernova Search) has successfully searched and blinked images using the powerful Seghal Supernova Search Tool in Maxim DL. It's included in one of Maxim DLs lower cost versions but still not cheap.

Also here is a link that maybe useful.
https://www.theastrogazer.com/home/image-blinking

Just found a blinking programme called GrepNova - I have never used it but it seems it is free and the link to the download can be found on this site. If you use it let me know how it works for you!
https://in-the-sky.org/software.php

Best,

Peter

[Swagman105]

Thanks for all the info everyone

One of the reasons for my going down the AP path was not necessarily only to produce pleasing images but actually to have the chance to discover something. Whilst I am not at the point I would like to be with my AP equipment and expertise yet, your info will be very helpful going forward.

Discovering something new is possibly a long shot but that's never put me off the joy of the hunt (An old gold prospector talking here).

Another reason is that some time back I promised my wife, in return for some freedoms to pursue my hobby, that if I was ever lucky enough to find a new comet or asteroid, I would name it after her. (providing of course it was not on an earth killing trajectory).

[bojan]

Also here:
https://fileforum.betanews.com/detail/Blink-Comparator/1124466644/1


EDIT: link mentioned above is dead..
But this one works:

https://download.cnet.com/Blink-Comparator/3001-2054_4-10428135.html

[Merlin66]

The attached images show CdC being used to search an image against the UCAC4 star database, in this case checking out Wolf-Rayet stars.

[Swagman105]

Wow Ken
That is amazing. I do not know a lot about WR stars but the most marked variabilities evident seem to be stars or objects other than the WR stars marked in the image. I presume therefore that those objects should be prime cases for further investigation should their variability not already be known, exactly what I was hoping for.
In CDC are you able to use two of your own images to compare other than using a standard star database such as UCAC4?
Geoff

[Merlin66]

Geoff,
If I just want to compare one image to another I could use the Astroart blink option.
If you want to identify something "new" I rely on the CdC background.