Support requests are handled via the support form so they can be tracked and resolved properly. This section is for community discussions about the AstroBin platform.
John Hudson avatar
What is the ideal resolution to upload to AstroBin so it looks best? Is there some kind of formula or preferred pixel dimensions?
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Salvatore Iovene avatar
I don't think there's a specific resolution that looks best. AstroBin will of course resize your image to various smaller size for optimal display in various places (as of course it doesn't make sense for the browser to download the full resolution to display it as a small thumbnail, for instance).

When it does so, it tries to keep the quality as high as possible and reasonable.

Ultimately, there are a couple of constraints:

1. Images larger than 16536 pixels on one size will always be scaled so that the long size is 16536 pixels
2. Images with a total number of pixels larger than 32768 x 32768 will not be accepted at all
3. Images larger than a total of 8192 x 8192 pixels will not be able to be zoomed in with the nice zoom, but you'll get your native browser display in a new tab

If you're looking for the "optimal resolution" that displays the best, I'm afraid that it doesn't exist, because it depends on factors that AstroBin or you cannot control, such as the properties of the device that the viewer is using.
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Quinn Groessl avatar
I prefer ones that are able to have the nice zoom that Salvatore mentions. I never knew the size limit, but from now on that's the largest I'll submit.
Salvatore Iovene avatar
Quinn Groessl:
I prefer ones that are able to have the nice zoom that Salvatore mentions. I never knew the size limit, but from now on that's the largest I'll submit.

I would recommend against that. Technical limitations are temporary, while images are forever, and at some point I might find a memory management trick to make the zoom work on larger images, and/or bump it up in the future as device get more and more powerful.

When that happens, the nice zoom will work on larger images too, but you are unlikely to come back and update your image with a higher resolution.
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John Hudson avatar
Salvatore Iovene:
I don't think there's a specific resolution that looks best. AstroBin will of course resize your image to various smaller size for optimal display in various places (as of course it doesn't make sense for the browser to download the full resolution to display it as a small thumbnail, for instance).

When it does so, it tries to keep the quality as high as possible and reasonable.

Ultimately, there are a couple of constraints:

1. Images larger than 16536 pixels on one size will always be scaled so that the long size is 16536 pixels
2. Images with a total number of pixels larger than 32768 x 32768 will not be accepted at all
3. Images larger than a total of 8192 x 8192 pixels will not be able to be zoomed in with the nice zoom, but you'll get your native browser display in a new tab

If you're looking for the "optimal resolution" that displays the best, I'm afraid that it doesn't exist, because it depends on factors that AstroBin or you cannot control, such as the properties of the device that the viewer is using.

I think my own answer to my question is probably that I need to shoot for lower rather than higher just for sharpness. Also full size tends to look a bit soft when re-scaled?
Salvatore Iovene avatar
John Hudson:
Also full size tends to look a bit soft when re-scaled

I've never heard this one, but the full size doesn't get scaled unless one side is longer than 16536 pixels.
Hartmuth Kintzel avatar
Salvatore Iovene:
Quinn Groessl:
I prefer ones that are able to have the nice zoom that Salvatore mentions. I never knew the size limit, but from now on that's the largest I'll submit.

I would recommend against that. Technical limitations are temporary, while images are forever, and at some point I might find a memory management trick to make the zoom work on larger images, and/or bump it up in the future as device get more and more powerful.

When that happens, the nice zoom will work on larger images too, but you are unlikely to come back and update your image with a higher resolution.

I disagree with Salvatore regarding image resolution.
Unless it is a large panorama image, I would always try to keep the image size such that the Astrobin zoom works.
It is much more comfortable for the viewer.
As a rule, a higher resolution does not result in better detail recognition.
In most cases, the opposite is true: when images are displayed at 100% resolution in a new window, image errors, image noise, and processing errors are more noticeable.
The viewer then has no way of adjusting the resolution to a suitable level.
This makes the images difficult to handle and it's no fun to look at them.

CS
Hartmuth
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Salvatore Iovene avatar
Hartmuth Kintzel:
Unless it is a large panorama image, I would always try to keep the image size such that the Astrobin zoom works.
It is much more comfortable for the viewer.

That's valid, but then if I'm able to bump up that maximum resolution to support the nice zoom viewer, it's a pity that images in the past had be uploaded at a smaller resolution.

I guess the best way for me would be to create a 8192x8192 maximum resolution image to use in the zoom viewer, and offer a button to view it at full size in a new tab for images that exceed that size natively!
John Hudson avatar
Salvatore Iovene:
John Hudson:
Also full size tends to look a bit soft when re-scaled

I've never heard this one, but the full size doesn't get scaled unless one side is longer than 16536 pixels.

I guess I should re-phrase. The view that one gets from the main image page, whatever it happens to scale to, where you can see the other details and plate solved etc. That image tends to be softer than if you were looking at it in Photoshop for example. But I think here are image sizes that may look better there, so I will experiment with it.
Salvatore Iovene avatar
John Hudson:
The view that one gets from the main image page, whatever it happens to scale to, where you can see the other details and plate solved etc. That image tends to be softer than if you were looking at it in Photoshop for example. But I think here are image sizes that may look better there, so I will experiment with it.

You're seeing an image that was 8000 pixels originally and scaled down to ~1800 pixels by AstroBin, then scaled again by your browser to fit to the available space depending on your screen resolution and window size. Depending on the image and your eye, it's perfectly possible that it looks softer or even the opposite, sharper.

Different browsers will use different scaling algorithm, you cannot control that.
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Hartmuth Kintzel avatar
Salvatore Iovene:
I guess the best way for me would be to create a 8192x8192 maximum resolution image to use in the zoom viewer, and offer a button to view it at full size in a new tab for images that exceed that size natively!

That sounds very good!

CS
Hartmuth
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