Sunday, November 24, 2019

Comparative performance of Tamron SP 24-70mm f/2.8 Di VC USD / Model A007N

I purchased this lens recently, but am planning to send it back.  Experience is below for anyone considering this lens, or wondering if their copy is good or bad.

Note: this post does not review the "G2" model of this lens.

First informal tests showed up a possible issue.

  • Handheld,  1/1000s or higher, high ISO.
  • No, the sign is not straight. Who cares, look at the results!

0 - Uncropped example shot









Yes, I know DOF plays a part.  But still obviously a possible issue.

So, on to more rigorous testing, below.

Note: I am aware it is not fair to compare a zoom against primes, a zoom at max zoom vs. a zoom at min zoom.  However, these are the lenses I had available.   All lenses were shot wide open to make the tests as fair as possible.

All at ISO 100, tripod, 5s self-timer delay, Nikon SB-24 flash, lens VR off, lens was refocused for every shot.

Test rig

Zoom vs. Zoom:  Tamron 24-70 @ 70mm, f/2.8 vs Nikon 70-200 @ 70mm, f/2.8:

Tamron 24-70 f/2.8 @ 70mm, f/2.8

Nikkor 70-200 f/2.8 @ 70mm, f/2.8

Similar focal lengths: Tamron 24-70 @ 70mm, f/2.8 vs Nikon 50mm f/1.8 @ f/1.8:
Tamron 24-70 f/2.8 @ 70mm, f/2.8

Nikon 50mm f/1.8 @ f/1.8

Third-party vs. Third-party:  Tamron 24-70 @ 70mm, f/2.8 vs Tokina 100mm f/2.8 macro @ f/2.8:

Tamron 24-70 @ 70mm, f/2.8

Tokina 100mm f/2.8 macro @ f/2.8
 It's obvious the Tamron is far worse than any of the other lenses.  Not what I would expect for this class of lens.

To be fair, I would not expect the Tamron to equal the Nikon 70-200 f/2.8 (which is legendary), the Nikon 50mm (also legendary) or the macro prime.  But for my money, since Tamron touts this as a premium lens, it should be better than this.

Tamron @ 70mm at different apertures (target ~ 80 cm away):

f/2.8 - Poor

f/4.0 - Mediocre

f/5.6 - Excellent, tack sharp detail

OK, so the lens is capable of good performance - just look at that lovely detail at f/5.6.  So it's unlikely to be damaged or defective.  It just has crap performance below f/5.0 or so.

Again, I'm not expecting a third-party zoom to be as good as a prime, or a Nikon zoom.  But the whole Tamron value proposition is to get 80% of the performance  for 50% of the cost. This lens doesn't live up to that.

Also, the whole point of buying a fast zoom is to shoot it fast.  You can't tell me "just" to shoot it at f/5.0 or lower.  What, the athletes are going to slow down because I ask them to?

I tested the lens for front/back focus but could not discern any differences at f/2.8, even at max adjustment in a Nikon D7200,  owing to the poor image quality.  I don't think this lens is compatible with a Tamron TAP-In dock, and it's unclear if any focus adjustment will correct this anyway.

Being a G1, my Tamron was used and so perhaps was not in the best shape.  However, if you're planning to buy one, you may want to test it first.

Thursday, November 21, 2019

How to transfer Terraria data to a new Android

Amazingly complicated tutorial here.

tl;dr version:  Copy the following directories from the old device to the new:


I suggest you also do directory "OldSaves" as well.  On my old tablet, "Players" and "Worlds" were both empty, probably because it was running an older version of Terraria.

The entire rest of the tutorial is a walkthrough on how to copy these up to a cloud drive, and back down again.  Obviously any equivalent method will also do. 

It seems Terraria used to have a cloud save function.  I don't see it in the latest version (as of Nov 2019) and have no idea if it still exists or not.

Migrating Android "Hunt Cook: Catch and Serve" data to new device

Thanks to original poster here

I didn't get the process at first, so I rewrote it with more detail below.

Note:  If you have already started HuntCook on your NEW device, uninstall and reinstall it.  DON'T start it again (yet).

1.  Start HuntCook on OLD device.

2.  If you haven't already set it up, it may ask you to allow access to your Google account. 

You have to permit this, as this is where the backup will be stored.

3.  In the HuntCook app, go to Menu->Settings->Data Backup.

4.  Proceed to back up your data. 

-  You will need to assign a password.  Make it a simple one unique to HuntCook - you don't want a data breach goofing up your real passwords.

-  You will get a cryptic 16-character "Backup ID".  Be sure to write this code down.

-  You will also get the option to take a screenshot.  You can do so but I don't know where it is stored.

5.  On the NEW device, start HuntCook.

6.  Tap "Restore data backup" button in the bottom right-hand corner.

(It may be called something else, I forget the exact button name.)

7.  Enter the cryptic 16-digit "Backup ID" you previously wrote down.  Don't enter the spaces.

8.  Also enter your HuntCook backup password.

9.  You get prompted two or three times to allow transfer of the data from your old device to the new device.  Confirm the transfer.

HuntCook will then import the data and deactivate the game on the old device.  Your new device is ready to go.

You will be warned several times that transferring the data will prevent the transferred gameplay from being played on the old device.  However, the app is not deactivated, and you can start a new game on the old device.