Lens data available on my server

[AllenR]

As I mentioned in a thread started by Darinwc, I have collected a fair amount of LF lens data over the past several years. That data is now available on my web site in a very basic form. The link below is to an overview document that explains what I’ve done and that contains links to the various pieces and parts. This is a work in progress and is far from being the perfect solution for a lens database, it is just my preliminary attempt at creating such a resource. I am sure that there is some duplicate information that needs to be cleaned up and a few things may be incorrectly categorized, but I hope the data is of use.

I have spoken with Sean about eventually making this data available on the APUG server in searchable database form. While he is very interested in doing this, his plate is full with the conference and the upcoming upgrade of the APUG site software, so it will be later in the year before we might be able to begin working on a move. So, for those who might be interested, here is the link

http://www.allenrumme.com/lensdb/DBIntro-1.html


Allen

 

[BrianShaw]

Allan... quite an impressive effort! Congratulations on pulling together all of this data and making it available. I look forward to the day when you/Sean have the time to integrate it into the APUG site.

A couple of comments (certainly not intended to be criticisms): check your spelling. There are a couple of typos such as "sereis" vs 'series' and "fell" vs 'feel'. These are easy to figure out the intent, but sometimes people start discounting the rest of the technical accuracy when these kinds of errors are found. (Trust me, I write techical documents for a living and hear this all the time. I also realize how difficult it is to accurately proofread ones own work!)

I LOVE the variety of information -- you have some data about lenses that I've never heard of. But several interesting omissions include Schneider lens from the 1980's and any Fuji lens data. If there was a cut-off date for which your current database, maybe it should be mentioned. Again... not a criticism... I understand the humongous effort involved in what you have done thus far and the near-impossible nature of putting together a 100% complete database.

Finally, thanks for the invitiation to contact you... have you considered adding a "mailto" or an email address to your 'dbInto-1' page?

Thanks very much for orgainizing your data into a coherent format. I look forward to looking over it in more detail -- there is a lot to be learned there!

 

[AllenR]

Brian,

Thanks for the feedback. I'll add the mailto link, good idea. As for the typos, given my dyslexic fingers, I don't doubt that there are some interesting misspellings out there. Coming from an R&D background, I completely understand your comments. I'll fix the typos as I find them or as they are pointed out to me.

As for a cut-off date, it was selected rather arbitrarily. There is already a lot of data that has been posted or published on more modern lenses (Kerry Thalmann's work comes to mind) and I didn't feel it was necessary to re-invent the wheel, or that it was appropriate to just included someone else's work in my database. I agree that including data on more modern optics would be helpful in rounding out the information. Maybe I can find time in the future to add this data.

Allen

 

[Dan Fromm]

Not to be impolite, but what does your list add to the information readily available -- for a nominal sum -- in A Lens Collector's Vade Mecum?

 

[JG Motamedi]

Many thanks for your excellent and useful list!

In response to Dan's question: While your list provides much of the same information in the Vade Mecum it is certainly more "user friendly", and perhaps will allow for corrections for some of the oversights, contradictions, and mistakes in the Vade Mecum.

In a related question, I note that for the most part you are relying on manufacturer specifications. While this is probably the best route to travel, there were quite a few changes over time as well as many under or overestimates regarding IC and even FL. For instance. Dallmeyer has printed that their 5D will cover 12x15 stopped down. I can tell you from personal experience with two of these lenses that this is not true. Or, a better known underestimate; The G-Claron series covers about 83 degrees, much more than the manufacturer's specs.

One of the flaws of the Vade Mecum is that it does not deal with these variations in a consistent and reliable way. How can this be corrected? Doing so would make your efforts all the more valuable.

 

[AllenR]

Not to be impolite, but what does your list add to the information readily available -- for a nominal sum -- in A Lens Collector's Vade Mecum?

Dan,

I started this effort well before the Vade Mecum was available. I was hoping that when I obtained a copy that it would fulfill my needs and I could stop this insane data entry task that I has set for myself. Unfortunately, the Vade Mecum was a bit of a disappointment, the technical data often being very general in nature and inconsistently presented. So, I kept on.

There is no agenda attached to my making this data available, I just thought some folks might find it useful. If you don't find it useful in this form, then by all means don't use it.

Allen

 

[AllenR]

One of the flaws of the Vade Mecum is that it does not deal with these variations in a consistent and reliable way. How can this be corrected? Doing so would make your efforts all the more valuable.

Yes, there are tons of inconsistencies in the data, regardless of the source. However, I think you have to start with some sort of baseline dataset and then layer on variations as gleaned from manufactureres data, reliable empirical data gathered from folks using a particular optic, as well as any other data that serves to clarify any inconsistencies in the baseline data. I think a database could probably be designed to accomodate this. How the data was organized and presented would require some thought, but it is doable.

Of course, it is easy to say that it can be done but it would require more resources than I can throw at it.

Allen

 

[Papa Tango]

Not to be impolite, but what does your list add to the information readily available -- for a nominal sum -- in A Lens Collector's Vade Mecum?

Well Dan, its online and its free. Not to mention that it will likely be updated and include new lenses (and old ones too!) without buying anything else.

 

[rbarker]

Excellent resource, Allen. Many thanks for your efforts in compiling this data.

 

[AllenR]

Thanks for the responses. While I know that there isn’t a huge amount of interest in this type of database, I thought I would post a couple of thoughts about the future of this data.

Several of you have asked if, and how, other data could be included to round out the information. I think this is something that would be nice to do, but probably needs to be discussed. Also, any major updates or additions would require more than just me working on it. I am, after all, supposed to be out making pictures.

Darinwc and I have had some conversations about lens databases, and we discovered that we have somewhat different ideas about what they might look like. Not that one idea is better than the other, just different. I am sure that there are other ideas out there as well. So if there is a desire to make this a more full-featured resource, and if there is interest, I would lobby that we form a small group who could work on defining how the data might be organized, on how to approach accommodating all of the variations seen during the lifetime of a particular optic, and on how to incorporate real-world observations of lens performance.

One other thought. When Sean is ready to entertain serving up this data on APUG, it would be nice to be able to hand him a completed application. What that application looks like, and how it behaves will also take some thought and, again, more than just me working on it.

Anyway, PM me if you are at all interested in working on this.

Allen

 

[bob01721]

DAY-um! That's quite the undertaking, Allen. Nice job!