How to make a mosaic from WW2 aerial survey photographs?

[JohnFraser]

The archives here on Ssipan, CNMI contain  a set of photographs from a 1945 US Navy or Army aerial survey of the entire island of Saipan.

My task is to combine them into a single photographic image file.

The photos are b&w and approximately 10" x 10".

The facility where the photographs are archived has a 600 dpi scanner.

I have access to the photographs only and not the original negatives.

Do you have any suggestions on the best way for me to proceed?

Thanks.

john

[JohnFraser]

Thank you for your comments and information.

The reference map is the esri World Image which esri makes available to anyone. World Image's spatial reference is WGS 1984 Web Mercator Auxiliary Sphere and I used that as the coordinate source for the images that were referenced to it.

The purpose of the mosaic is to provide visitors, including researchers, to the CNMI Archives with a view of Saipan in 1945. I don't know what kind of accuracy and precision they will need. The archives curator says people ask for that sort of thing from time to time.

I would at least like what you might call a nice qualitative map. The more accurate and precise, however, the better for researchers who might want to make measurements or take data from the map.

For reference points, there are a fair amount of coastal features that seem to have remained stable since the aerial survey 70 years ago. In addition, there are some Japanese concrete buildings and fortifications which are still here. I've also used road intersections which in some cases are dead on but in others have moved.far enough that I've had to throw them out as references.

To get an estimate of the photo scale, I measured across a large feature, Laulau Bay, on the scanned map and compared it a Google Earth measurement. The scale looks to be about 1:30,000.

BTW, I recently got a hold of a government sponsored Lidar survey of Saipan and am considering including contour lines on the final product if that's possible. I am also wondering if I could make the Lidar my reference map.

Thanks again.

john

[SepheFox]

That's absolutely possible. You can put any features over your map you wish, and contours are relatively easy to make from LiDAR. As far as a spatial reference goes, you may want to reproject your data (using the project tool) at some point into a local coordinate system. I'm not sure what that might be for Saipan, but it would be better for any kind of analysis or measurements. You will probably find that, indeed, the LiDAR will already be in a local projection, likely whatever the government standard is. Good luck! You've done well so far.

[DanPatterson_Retired]

​given potential changes in what you have to georeference too, I wouldn't bother, the images are important in themselves and the benefits gained would not be much.

[JohnFraser]

Thanks Dan. See my reply to Sephe above.

john

[PeterBecker]

Note there will be a Demo Theater at the User Conference. 'Best Practices for Managing Historical Imagery'

Tuesday, 21 Jul 2015, 10:30am - 11:15am

Location: Demo Theater 12 - Imagery

This will provide detail on a workflow to create a mosaic dataset based on the a feature class of approximate center coordinates and then use some of the more advanced tools such as block adjustment to help automate the  image to image matching and then also add control. Control to refine the coordinates can come from any source including the World Imagery. The resulting mosaic dataset can be directly used in ArcGIS for Destkop or served as an image service making the imagery and any available metadata accessible.

[JohnFraser]

Hi Peter,

Thanks so much for your reply.

Unfortunately I can't afford the fee for the User Conference unless you

know of a scholarship or grant that I could apply for. l live on Saipan in

the Western Pacific and it is also pretty expensive to get there.

Hopefully there will be information online about the new feature and

workflow after the conference. If you have any emailable material or url's

I would appreciate you sending them.

Thanks again.

Best regards,

john

[PeterBecker]

John

We will make sure the slides and notes from this go on to the resource center soon after the UC and will post a note about it back here.

[JohnFraser]

Peter,

That's great. Thanks so much.

Best regards,

john

[PeterBecker]

The following link will now got to a new 'Historical_Imagery_GP_Tools' item on ArcGIS Online.

It is part of the Image Management Workflows Group ​

It includes documentation on a recommended workflow, the slides from the User Conference presentation as well as some GPTools to help automate some of the processes

[JohnFraser]

Thanks. I downloaded the Python toolset. which had a .pyt extension. I wasn't sure what to do with it so I dropped it into the Python window in ArcGis 10.3. It created a couple lines of ?instructions but nothing came of that.

I then dropped the .pyt file into the Python GUI window (2.7.10 shell) in Python 2.7. That created a lot of what looked like ?instructions but I didn't know what to do with them. Could you tell me what to do with the toolset? Thanks and best regards.