Hidden Treasures Competition


ESO's Hidden Treasures 2010 astrophotography competition is now closed, but stay tuned for future editions!
You can check the 2010 winners here.

Watch an ESOcast episode on how the competition was done!

All the entries have also been uploaded in a Facebook album.


What is it?

Are you ready to dig through the whole archive of observations
from ESO's best telescopes, and bring out hidden treasures?

1st Prize

Trip to Paranal + goodies

2nd Prize

iPod Touch + goodies

3rd to 10th Prize

Eyes on the Skies Book + DVD + goodies

Deadline: November 30, 2010

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Detailed instructions
Archive query form
Flickr upload

Browse the archives!
Step 2: Join Flickr
& upload Photos


The European Southern Observatory (ESO) is proud to present “Hidden Treasures” — a free competition for everyone who enjoys making beautiful images of the night sky using real astronomical data. The competition has some extremely attractive prizes for the lucky winners who produce the most beautiful and original images, including an all expenses paid trip to ESO's Very Large Telescope (VLT) on Cerro Paranal, in Chile, the world’s most advanced optical telescope. And the winner will have a chance to participate in the nightly VLT observations under the crisp Chilean skies.

Are you ready to dig through this huge collection of images from some of the best telescopes in the world, and reveal its hidden treasures? This is not for the faint-hearted, as many terabytes of data are available, spanning many years, different instruments and technologies. The individual files in the archive are each single exposures, obtained through a single filter. They need to be extensively processed and combined to bring out the beauty hidden in there. Will you compete with the very best astrophotography specialists?

The entries should be submitted via the Flickr group before November 30, 2010.

They will be judged on the bases of their aesthetic and technical qualities, and on their originality. The winners will be announced in December.


The goal is to mine the publicly available ESO Science Archive to select a set of data frames, process them, and assemble them in a final colour or greyscale image. There is no restriction on the number of individual frames combined, on the number of filters — or instruments — you can use. Data processing and enhancing is of course allowed, although altering local details to make aesthetic improvements is not allowed (“painting” in the image); only corrections of defects and blemishes are allowed.

The images submitted should not directly duplicate an existing image available in the ESO galleries. If the submitted image is of a celestial object of which an image is already available in the gallery, then make sure you use data from a different instrument.

The entries will be judged on the basis of their aesthetic and technical quality and originality. The full, detailed rules are available here.


A number of very attractive prizes are offered by ESO. The first prize includes an all expenses paid trip to visit ESO's Very Large Telescope, on Cerro Paranal, Chile. The best images will be published world wide on our website.

1st Prize

    1. A trip to visit the Very Large Telescope at ESO's Paranal Observatory, in Chile, for one person, including intercontinental and local air fare, ground transportation, food and lodging, guided tours including an overnight stay with participation in the observations at the VLT. The winner agrees to follow ESO’s rules and regulation during the visit
    2. A high quality 60 cm mounted print of the winning image
    3. A laser-engraved glass cube with a model of the VLT
    4. The book Eyes on the Skies including the Eyes on the Skies DVD
    5. A set of ESO posters

2nd Prize

    1. A laser-engraved glass cube with a model of the VLT
    2. An iPod Touch, engraved with the ESO logo
    3. A high quality 60 cm mounted print of the 2nd prize image
    4. The book Eyes on the Skies including the Eyes on the Skies DVD
    5. A set of ESO posters

3rd Prize

    1. A laser-engraved glass cube with a model of the VLT
    2. A high quality 60 cm mounted print of the 3rd prize winning image
    3. The book Eyes on the Skies including the Eyes on the Skies DVD
    4. A set of ESO posters

4th –10th prizes

    1. The book Eyes on the Skies including the Eyes on the Skies DVD
    2. A set of ESO posters


  1. Identify and retrieve a data set from the ESO Science Archive (see this page for instructions). Once you have requested the data, they will be extracted from the Archive, which can take a few hours. You will then receive an email with the instructions on how to transfer the data.
  2. You can process the data in any way you want, and combined them as you wish. The first step is to de-bias and flat-field the raw FITS image, then — if needed — combine several images to increase the depth and/or field of view. The end or intermediate results can be enhanced using any technique. The only thing that is strictly forbidden is to “paint” on the images, for instance using a paintbrush. Only cosmetic defects can be removed by “painting”, such as cosmic rays, bad pixels, satellite trails, etc.
  3. Once you have produced an image you are pleased with, save the original file in your working format (for instance .psd for Photoshop, or .xcf for GIMP), and generate a moderately sized JPEG for submission. The instructions on how to submit your entries are listed here. Keep the full sized file as we will want to look at this if you are shortlisted.


We are fully aware this is a complex and time consuming challenge. This is reflected in the nature of the prizes. For enquiries about the competition, you can contact us at hiddentreasures@eso.org.