Focus Problems. No images/No surface/Not enough focus

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fjgiie
DustMod
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Location: Hampton, SC, US

8827505V1

Post by fjgiie »

Hi Dee,

Do you want the good news first or the bad news first? :)
Here is what I think:

Movie 8827505V1not movie 8827505VI is Bad Focus. This means what you found is a speck of surface dust. So this is the good news, as you marked it correctly - No Track - It could have been marked Bad Focus also, which would have been more nearly correct.

We don't like bad news so there isn't any today.

Thanks,

fjgiie
daveb45
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Joined: Fri Aug 11, 2006 6:35 pm
Location: Sloughhouse, CA

Post by daveb45 »

On the last calibration movie I got with a track I noted the track wasn't really definite until 12 frames below the surface. Is the focus increment different on the calibration movies or have I not been liberal enough with the bad focus calls?
DustBuster
DustMod
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Location: Horsetown, USA

Post by DustBuster »

daveb45 wrote:On the last calibration movie I got with a track I noted the track wasn't really definite until 12 frames below the surface. Is the focus increment different on the calibration movies or have I not been liberal enough with the bad focus calls?
Hi Dave.

I have also noticed the calibration of the focus bars is NOT the same for every movie. I don't know how to tell if it's different for each batch of movies (tile scanned) or if it can vary even in a single scanning session.
I share your concern about being liberal enough, and as a result I find myself re-calibrating my definition of 'bad focus' quite often.
Use your best judgement with the knowlegde you've gathered and the tools you've been given- you can't go wrong.
No dessert for you- ONE MONTH!
Dee
Posts: 12
Joined: Fri Aug 18, 2006 10:03 am
Location: VANCOUVER, CANADA

8827505VI

Post by Dee »

Thanks, fjgiie,

We have reached the same conclusion...dee
rstone
Posts: 1
Joined: Mon Oct 09, 2006 8:29 am

Post by rstone »

I feel like I'm wasting my time here. What I have determined is this:

A: virtually ALL of the calibration images focus on the surface at or above the middle of the focus range, and

B: virtually ALL of the real images focus the surface BELOW the mid range.

I am wondering how many dust tracks will be (or have been) missed because of this.
fjgiie
DustMod
Posts: 1253
Joined: Sat May 20, 2006 8:47 am
Location: Hampton, SC, US

Bad Focus

Post by fjgiie »

Hi rstone,
Here is the link for when to use the Bad Focus button:
http://stardustathome.ssl.berkeley.edu/ ... .php?t=645

The project called Stardust at home will take some time to complete. After going through all the focus movies that are made first, we will need to look at the remade bad focus movies. If members will click Bad Focus on a movie that is bad focus, no tracks will be lost as we will get the chance to take another look at these movies. Also the edges of most of the tiles will need to be rephotographed because the focus was so bad on these edge movies, or they decided to just go ahead and photograph the flat center and come back later for the rounded or sloped edges.

We now have 16, 000 members. The scientists estimate that there are 45 IS dust tracks in the Aerogel. We may not find all of them. So 16,000 members divided by 40 tracks = 400 members per track. That means that only one member out of every 400 will find a track, or be the first to click on a track. What we as members need to do is use the tools supplied to us to help the Stardust at home team find these tracks. When we see a track, click on it. When a movie is bad focus, click Bad Focus. These movies will be remade.

Thanks,

fjgiie
tk210_00
Posts: 2
Joined: Mon Oct 23, 2006 3:15 pm

Post by tk210_00 »

Has anyone noticed alot of these new movies seem to focus wrong , on some of the movies , as you focus up or down the image shifts left-right or up-down , is this on purpose or a camera issue?
DustBuster
DustMod
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Joined: Wed May 17, 2006 8:12 pm
Location: Horsetown, USA

Post by DustBuster »

tk210_00 wrote:Has anyone noticed alot of these new movies seem to focus wrong , on some of the movies , as you focus up or down the image shifts left-right or up-down , is this on purpose or a camera issue?
Hi tk.

There may be a number of differenct causes involved, including; lighting, camera height, titled surface, as well as a bad group of scans you are getting a look at; but I have not noticed it to be any more prevalent than usual.
danajohnson
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surface texture, debris, and movie depth levels

Post by danajohnson »

I was surprised to see that it appeared the areogel material was cast with the Back or Bottom side as we view the 'slide' or 'container' in the movies to the far or bottom depth of our movies.
I would think the better technique would be to cast the material with the 'upper' or particle entry point to be the base of the original casting so as to produce a very flat objective measuring point for depth calibration. Was this done, and is the surface as we see the "surface" here in movies actually the best flat casting that was possible at the time of construction?
Not to be critical, but, second guessing the technique none-the-less, as I also have a large list of movies which are ranging from twenty levels to thirty levels below the apparent photographed visible 'surface', at which depth the halo becomes clear and soundly judged.
It seems probable that the levels should have been been greater in number than forty to catch all event items available. Could the process be adapted to a deeper set of levels later?
Was the viewed 'upper' surface the actual casting bottom, or the cast top?
Together our field of view is greater. Sincerely, Dana Johnson - danajohnson0
danajohnson
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Joined: Wed Jun 14, 2006 9:43 pm
Location: P.O.Box545,OKC,OK,US,73102
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surface texture, debris, and movie depth levels

Post by danajohnson »

To answer my own suggestion and to contradict the idea of casting against the upper surface: I use the debris and the surface roughness to focus on, and it works better than guessing at the depth location of the featureless surface of some movie sets. Also the debris at the bottom would be entering into a focused and more contrasty condition in direct competition with the tubular lower impact shapes which show up as dark 'halos'. Unless they were very deep movie 'stacks', the debris would appear to be possible track locations.
Keeping stray particles out of the main mass is also a good aspect of the technique being used as has been done here.
I usually click as a bad focus movie set any with a surface below the last ten levels. Perhaps I should have struck down any focused lower than the level the team marked as a standard?
Together our field of view is greater. Sincerely, Dana Johnson - danajohnson0
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