Tony Northrup

Tony Northrup

Lives in United States Waterford USA, United States
Works as a Photographer/author
Joined on Jan 6, 2002
About me:

Check out my book, "Tony Northrup's DSLR Book: How to Create Stunning Digital Photography":


Total: 16, showing: 1 – 16

Awesome article, Rishi. Brave, too; nobody knows better than I how mathing crop factor and equivalence enrages people (yet accurately predicts performance).

The recent medium-format craze is reminiscent of the micro-four thirds craze almost a decade ago. Remember when everyone was excited to see tiny MFT 12-35 f/2.8 lenses that produced the same results as huge FF 24-70 f/2.8 lenses? That misconception launched an entire industry, and buyers spent millions assuming they'd get results that were simply impossible.

I do think the new medium format system cameras are compelling for reasons like the Fuji's interchangeable viewfinder, which is useful and needed. But most people seem to be buying into it for "separation" and "compression" and "that medium format look"... reasons that just don't exist.

Link | Posted on Mar 21, 2017 at 12:35 UTC as 399th comment | 17 replies
In reply to:

Marko2: Does it suffer from focus breathing like its predecessor?

To a much less extent. It's still not quite as long as close range as the Canon or the Sony GM, but it's MUCH longer than the previous Nikon. It's good enough that we switched back to Nikon for portraits.

Link | Posted on Feb 2, 2017 at 12:56 UTC

This seems almost identical to the Flashpoint XPLOR 600...? Weird that they have two similar wireless monolights. Did they just decide to rebrand a different third-party light?

Link | Posted on Feb 1, 2017 at 22:25 UTC as 7th comment | 4 replies

Too bad they didn't stick with it! This is like discovering that someone invented flight in 300BC but dropped it because it wasn't as fast as a horse.

Link | Posted on Dec 22, 2016 at 13:07 UTC as 28th comment | 3 replies
On article LensRentals tests the Nikon 70-200mm F2.8 FL ED (110 comments in total)
In reply to:

(unknown member): I wonder what the effective focal length at 200mm and minimum focus distance is, the previous version was really only 135mm.

We've been testing this lens. Focus breathing is almost completely solved... it's much longer at headshot range than the f/2.8G lens. It's *almost* as long as the Canon 70-200, but not quite.

The focus breathing fix is the biggest improvement. The lens also has much better contrast in heavily backlit scenarios. As this test pointed out, we didn't see much difference in sharpness, especially not in real-world scenarios. We'll have a video posted soon, maybe today.

Link | Posted on Nov 22, 2016 at 14:29 UTC

I must be the only pixel peeper on the planet who has never, ever felt the need to do a lens microadjustment. I work with shallow depth-of-field and I use a constantly changing assortment of sharp, fast lenses and high-megapixel bodies.

Have I just been incredibly lucky, or is this an over-diagnosed problem?

Link | Posted on Jan 22, 2016 at 22:48 UTC as 14th comment | 17 replies

Measure the T-stops, por favor!

Link | Posted on Dec 9, 2015 at 13:31 UTC as 96th comment | 1 reply
In reply to:

straylightrun: Does the a7sII focus with adapted DSLR lenses as fast as the a7rII?

Yeah focusing is pretty bad with it. I mean, sometimes it focuses successfully, but it's so hit-or-miss that I prefer just manually focusing + focus peaking and zooming as necessary... it's slower, but at least I know it won't be fruitless, as AF often is with that body.

Link | Posted on Oct 15, 2015 at 16:14 UTC
In reply to:

adengappasami: All shots at 1/100 and above. One shot at 65K ISO is not ever required for it looks slightly over exposed. At this viewing size i guess its almost similar to A7R II upto a point. May be post that 105K ISO things will look better.

I have the A7RII and i personally dont want that 42MB files. I am waiting for images from the A7SII in lowlight to compare with A7RII and probably switch.

We did this testing and the a7S II produces the cleanest video and stills at high ISOs that we've ever tested (and I believe we've tested every potential competitor short of $100k+ 65mm digital video cameras).

Link | Posted on Oct 15, 2015 at 16:13 UTC
In reply to:

SKPhoto12: Too bad, but an expensive modern camera that overheats when shooting video!!!! No way.

We were at the same event and I ran the a7S II for more than an hour at the top bitrate and it didn't overheat. I recall it got to about 117 F.

We *did* make the a7R II overheat in our testing, but we've been filming both short- and long-format recordings with it ever since and it's never failed in the real world. IMO, the overheating thing is overblown.

Link | Posted on Oct 15, 2015 at 16:11 UTC
On article Opinion: Bring on the 70-200mm equivalents (347 comments in total)
In reply to:

JoEick: This article is very misleading.

If the point of the article is to tell the reader how a 50-150 works similar on APS-C to 70-200 on full frame, then there needs to be more thought put into equivalent apertures.

You need f2.8 on crop to roughly equal f4 on full frame. The Fuji f2.8 zoom has no meaningful size or weight savings over a Canon 70-200 f4.

Until we see more f1.8 and f2.0 zooms for APS-C, there is nothing that compares in light gathering for full frame f2.8.

There is no free lunch when it comes to light, physics, and lenses.

Love the article! I'm with Joe; give me an APS-C 50-150 f/1.8 or MFT 35-100 f/1.4 so I can truly get FF equivalent results. I know it'll have to be big...

Link | Posted on Sep 20, 2014 at 13:48 UTC
On article Fujifilm announces weather-resistant XF 50-140mm F2.8 (226 comments in total)
In reply to:

attomole: Suspect the equivalence brigade will be out gunning for this, There is still nothing that sucks up light like the big 2.8 zooms for full frame that have been the backbone of professional photographers kit for years, and in comparison this is bit big and a bit expensive.

Yeah, came here to say this. The article says, "essentially equivalent to a popular 70-200mm telephoto zoom on full frame," and that's true, but it's equivalent to the popular 70-200 f/4 in terms of depth-of-field (important for the portraiture this will be doing) and total light gathered... it's not equivalent to the much more popular 70-200 f/2.8 lenses.

Still, I love Fuji, and we're getting closer to my dream 50-150 f/1.8 APS-C lens that will let me finally toss my DSLRs...

Link | Posted on Sep 10, 2014 at 11:48 UTC

After your excellent article on equivalence, I'm surprised to see that you're still showing the 35mm equivalent focal length without applying the crop factor to the f/stop number. Obviously this tiny lens isn't equivalent to a 21mm f/2.8.

By all means, list the physical f/stop and focal length. If you apply the crop factor to the focal length, however, you should also give us the equivalent f/stop.

Here's a good explanation:

Link | Posted on Aug 29, 2014 at 14:26 UTC as 8th comment | 4 replies
On article What is equivalence and why should I care? (2407 comments in total)
In reply to:

Death89: Not sure myself why this causes so many issues. Even before my purchasing an FZ200 for its F2.8 throughout the zoom I was aware of the equivalence of the dual nature of F numbers, etc. so I knew a 1/2.3 sensor equipped f2.8 superzoom was never going to reach the levels of DOF/Low-Light greatness of a full frame camera.

Really enjoyed reading the article though and now have a better idea of how it all works!

fredrious, that FZ1000 video is maddening. I wish they hadn't disabled comments. Evil marketing.

Link | Posted on Jul 7, 2014 at 12:32 UTC
On article What is equivalence and why should I care? (2407 comments in total)

Great article! Now, if we can just get manufacturers and press to list the full-frame equivalent apertures any time they list the full-frame equivalent focal length, we'll make camera and lens shopping much more honest.

One point: You're right that equivalent ISOs (found by using the crop factor squared) aren't as perfect as equivalent focal lengths or apertures. But, when comparing similar sensor technology, they're pretty similar. In my tests, crop factor accounted for 99.2% of the differences in ISO, and only 0.8% was attributable to differences in technology.

It seems to be > 99% accurate when comparing Sony, Nikon, and MFT sensors. Canon is a bit behind, but the crop factor squared formula still holds up when comparing Canon sensors to other Canon sensors.

Link | Posted on Jul 7, 2014 at 12:25 UTC as 480th comment | 2 replies

Perhaps you guys could start providing the full-frame equivalent apertures if you provide the full-frame equivalent focal lengths? This video explains why.

The SH-1 has about a 5.5x crop factor. The lens is physically 4.5-108mm f/3.0-6.9, so the 35mm equivalent is 25-600mm f/16-38 in terms of total light gathered by the sensor, light gathered by each pixel, and depth-of-field... all the factors that impact final image quality.

Link | Posted on Mar 31, 2014 at 15:57 UTC as 15th comment | 9 replies
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