HD Pentax-DA 55-300mm F4-5.8 ED WR Review

Construction and Handling

We've touched on a few of the different aspects of the lens' construction in the previous pages regarding what had and had not changed. Here are a few other key physical components of the lens to provide a bit more understanding of the optical instrument you are pondering over.

Lens Body

Like we delved in with quite a bit of detail in the "What's New" page, the grip on the barrel is very well made and despite a different take on it as compared to the previous version, we found there to be no change in the already excellent build quality. If anything, especially when mounting and unmounting the lens from the camera body, it was easier thanks to the slightly beefier base as compared to its predecessor.

Zooming

In the below animated .gif, we show the full extension of the lens, which has a rather large telescoping barrel extension:

There were some concerns with lens wobble with the previous model, as the long telescoping tubes sometimes shifted (slightly) in the housing. It thankfully didn't necessarily detract from the image quality of the lens, as severe wobble has the ability to decenter the glass elements inside, throwing the precision and plane of focus off. It was mostly a peace-of-mind issue amid concerns of possibly acquiring the all-too-feared QA/QC-escapee off the assembly line.

With regard to the HD 55-300, if there's one thing that was immediately present upon giving the lens its first spin (no pun intended), is that there is no wobble. Either because of the seals or just tighter tolerances in the build quality (our guess is a combination thereof), it's actually one of the stiffer zoom rings we've used. Not in a bad way, and once you mount it on the camera it has the perfect level of torque resistance.

Some lenses come with the claim that lens creep (or the auto-zooming of the lens due to its own weight under gravity, causing unwanted extension when not in use) is nonexistent. With the HD 55-300, we're claiming it's impossible.

Size Compared to Other Pentax Lenses

In the below animated .gif, we compare the stowed away (lens hood reversed), lens hood attached regularly, and full lens barrel extension positions and sizes of the following lenses, from left to right: DA* 60-250, HD 55-300, DA 18-135 WR, and DA 10-17 Fisheye. Yes, we realize that the fisheye lens in no way relates to any of the other three lenses, however it is nearly identical to the DA 18-55 WR kit lens (minus the 18-55's petal hood), which we did not have on hand for this review. The purpose for the 'DA 18-55' addition is because it is often used as part of a very capable two-lens kit with the DA 55-300, and one we highly recommend if the DA 18-135 WR is out of your budget.

As you can see, the HD 55-300, while quite a bit larger than the other lenses to its right, is dwarfed by the constant F4 lens to its left, especially when you take into consideration the (thankfully removable) tripod foot. It is interesting to see that the lens, with its hood attached, is exactly the same height as the retracted DA* 60-250 without its hood attached (or attached in the stowed/reversed manner). The draw of the HD 55-300 becomes obvious towards not only photographers without the ability to justify the steep price difference between it and its big brother, but those whom are space- and weight-conscious, especially while traveling or hiking.

If you look closely at the above animation and watch the focus ring of the HD 55-300 during each of the stages, you will notice that it does not change despite zooming in or out. This proves that the HD 55-300 is parfocal, which means that no matter the focal length zoomed to (in or out), the focus will not change as a result of zooming and thus require refocusing. Our use of the lens and zooming while looking through the viewfinder also confirmed this. This is especially important not just for sports/wildlife shooters quickly changing their magnification of a subject in motion.

In practice, we found that the focus wasn't exactly maintained when zooming and would require very micro adjustments. Nothing major, but it isn't perfectly parfocal and thus might be an issue for videographers.

Focus Extension

Some lenses offer internal focusing, which means that the lens does not expand or detract the lens body, but rather doing so inside the housing itself. One negative side effect of this is the pronounced effect of 'focus breathing,' which reduces the inherent level of maximum magnification at any given measured focal length the shorter the focus distance is. Only at infinity will the true magnification of the focal length indicated be realized, making it seem like you are being 'cheated' at closer focus distances of some valuable focal length mm's.

The DA* 60-250 is perhaps the most prominent example of this phenomenon in the Pentax line-up. Thanks to the HD 55-300's external focusing, it escapes relatively 'unscathed,' and we'll explore in-depth what that means in the following pages where we devote an entire section to the magnification differences between the two lenses.

In the below animated .gif, you can clearly see the extension created by the long focus throw. We used both the smc and the HD variants of the DA 55-300 to allow simultaneous comparisons of the effect the extension has while at its shortest and longest focal lengths (55mm and 300mm, respectively) as compared to each other and the DA* 60-250:

Additionally, the above animation is proof that the front element does not rotate when the focus ring is turned (automatically or manually). This is especially important to photographers that are keen on using filters.

Lens Hood

We considered putting this in the "What's New" section, but the difference is the most trivial of the entire smc to HD remake, so we decided against it. Instead, we'll touch on it here while addressing how the lens hood works. Can you spot the difference?

It wasn't until both windows above were removed and we were trying to put them back that we noticed a difference. The final letter in the name has been changed, from the smc's PH-RBG to the HD's PH-RBI (yes, the order is reversed above). We have no idea as to why, or what those letters actually mean. Additionally, you may have noticed it above, but the paintjob on the outside has been given a slight texture to it, but you wouldn't notice it by feeling them - there's no tactile difference between the two. At the end of the day there is 100% no considerable difference between the two hoods.

So by now you may be asking yourself, "What is that thing, and why would I open the side of a lens hood?" The below image demonstrates exactly how this looks in practice when the hood is mounted:

Have you ever attempted to rotate a circular polarizer lens while having a lens hood attached? While looking through the viewfinder to see the affect? Well, it's impossible, thus requiring you to remove the lens hood, adjust the polarizer, and then re-attach the lens hood. Ingeniously, Pentax has been offering this window in all their detachable lens hoods (except the lenses that can't allow for it, such as the Limited line of lenses thanks to their metal and often embedded 'sleeve' type hoods). We would expect this out of something like the DA* line of premium lenses. The fact that Pentax continues to bring this innovation to even the consumer line of lenses is nothing short of superlative. No one else in the camera industry has this standard, not even in their premium lenses, and we applaud Pentax for this touch. If this doesn't exude the impression, "For photographers, by photographers," we don't know what does.

Reversed Lens Hood for Storage

Lastly, here's an animated .gif showing the lens hood unattached and attached in its reversed/stowed away position. As you can see, it is extremely compact, adding a negligible amount of girth to the lens, thus making it a piece of kit never to be considered as something to leave behind and not use.

In short, the overall build quality, especially when you combine it with the weather sealing addition we previously covered in the "What's New" section, is nothing short of excellent. Especially for the price of this lens and what is available from the competition.

Now let's examine what the smc vs HD difference is all about.