The Interfit S1 is an affordable 500Ws, AC/DC powered monolight with high speed sync and TTL for Canon and Nikon cameras. The head is powered by a high-capacity 4500mAh Li-Ion battery which provides up to 350 full power flashes in Manual and TTL modes and over 400 full power flashes in high speed sync (HSS) mode. Firmware updates now available here ... More
Interfit S1 Twin Head Kit
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The Interfit S1 is an affordable 500Ws, AC/DC powered monolight with high speed sync and TTL for Canon and Nikon cameras. The head is powered by a high-capacity 4500mAh Li-Ion battery which provides up to 350 full power flashes in Manual and TTL modes and over 400 full power flashes in high speed sync (HSS) mode. Firmware updates now available here http://interfitphotographic.com/s1-firmware-updates/.
Key Features: Interfit S1 Twin Head Kit
New firmware update available – Unlock the pull power of the S1!
Interfit engineers are pleased to announce their latest firmware update that bundles together enhanced Canon 5D Mk IV compatibility and two additional stops to the bottom of the power range, read more here: Interfit S1 Firmware update!
Each Interfit S1 comes standard with both battery- and AC-power sources. The interchangeable 4500mAh Li-Ion battery provides up to 350 full power flashes in Manual and TTL modes and over 400 full power flashes in High Speed Sync mode. This wire-free power source gives photographers the freedom and mobility to venture out from the studio and rapidly set up and reposition lights on location. For traditional studio work, the S1 also ships with an AC power pack, an industry first for an advanced TTL/HSS battery-powered monolight. This multi-voltage adaptor can be used anywhere in the world (100-240v) and lets photographers continue to shoot while their battery is charging.
The S1 has three different shooting modes, each to serve a different purpose and shooting style. Interfit’s new S1 Remote for Canon or Nikon enables photographers to take advantage of their camera’s TTL system just like they would with a speedlight. This automated light output uses the S1’s entire 9-stop power range (500Ws – 1.9Ws), is automatically calculated in 1/10th stop increments, and allows for +/- 3 stops of exposure compensation, manually adjustable within 1/3rd of a stop. Having an automated flash exposure allows the photographer to quickly and easily achieve their vision. This automatic mode is ideal for environments with constantly changing ambient light, and shoots that require you to quickly change your setups or location.
For those that prefer to have complete control over their light and have time for fine-tuned adjustments, the S1 can be used in the traditional manual mode. Manual shooting mode also utilizes the entire 9-stop power range, controllable in 1/10th stop increments. While in manual mode, users gain access to the S1’s High Speed Sync mode, reaching shutter speeds up to 1/8000th of a second. High Speed Sync mode utilizes the top 4 stops in the power range (500Ws - 62.5Ws) and is manually adjustable in 1/3rd stop increments.
Utilising IGBT technology, the S1 is able to offer short flash durations while maintaining color accuracy throughout the power range. Flash duration ranges from 1/1,000 at full power, down to 1/9,000 at minimum power. By shortening the flash durations, we were also able to improve color accuracy, giving the S1 a consistent 5700k (+/-100k) color temperature throughout the entire power range.
S1 TTL Remote:
The S1’s TTL remotes give the users direct control over any S1 light in any shooting mode from the camera position. This camera-mounted transmitter is available for both Canon and Nikon camera’s and supports E-TTL ll and i-TTL protocol, respectively. Having three individual groups gives users the freedom to control lights individually to create dynamic lighting ratios with a working range of up to 100m (300’).
Interfit S1a - AC-powered flash:
The S1a has all of the same features as the S1 sans battery. This unit is designed primarily for use in studio or for photographers who have already invested in external power packs with sine wave inverters. Slightly smaller than the S1, the S1a works seamlessly with its battery-powered counterpart at a 40% lower price point.
We made durability our priority for our portable flash units, so we built the S1 and the S1a within a strong and lightweight aluminum body rather than plastic. We also include a frosted glass diffuser dome to protect the flash tube. Both the S1 and S1a feature the widely-used Bowens S-Type modifier mount, giving users hundreds of high quality and affordable modifier options to choose from including Interfit’s line of softboxes, reflectors, grids, beauty dishes and more. A mini-USB cable is included with every light, allowing for firmware updates when new cameras are released.
Maximum Watt/Seconds: 500Ws
Guide Number 100ISO, 1/125sec., 3m (10’): 48.7m (160’)
With our no deposit Buy Now Pay Later option, pay nothing for six months when you spend £250 or more, then either settle the cash price in full by paying a £29.00 settlement fee, or choose to spread the cost over 36 months at 19.9% APR Representative. Please see the repayment example below to see how much purchasing this item on finance would cost.
Item Value (Cash Price)
Total Amount Credit
35 x £50.89
Total Amount Payable
Annual Rate of Interest
Are you eligible for finance?
Applicants must be:
Aged 18 years or older from the application date
In permanent UK residence for a minimum of three years
Fulfil at least one of the following employment criteria:
In regular, permanent employment.
Retired from regular employment - With a minimum age of 50.
Not working through disability.
Note: All applicants will be subject to a credit reference check by the lender.
Credit is subject to application and status. Warehouse Express Ltd trading as Wex Photographic act as credit broker and not the lender. Barclays Partner Finance act as the lender.
Can I repay early? If so how?
No repayments are scheduled in the initial six-month deferral period. However, it is possible to pay off the loan, either by way of a lump sum or in smaller amounts. If the loan is fully repaid within the six-month deferral period, then no interest is payable, but a £29.00 early-settlement will be incurred. Such repayments may be made to Barclays Partner Finance by cheque, debit card or standing order. Unfortunately it is not possible to set up a direct debit within the deferral period. Further information on how to make such repayments will be set out in the loan agreement pack provided by Barclays Partner Finance.
What happens if I don't repay within the first six months (deferral period)?
Following the six month deferral period, Barclays Partner Finance will initiate a monthly direct debit payment for the remaining duration of the loan. Interest will be charged at a rate of 19.9% APR on outstanding balances (backdated to the first date of the loan). Late payment penalties and early repayment charges will apply from this point. Barclays Partner Finance will send a reminder letter approximately one month before the six month deferral period is due to elapse. Note: If you chose to spread the cost and pay monthly, interest is charged from the start of the loan, not from the start of the repayment period.
What will I receive from the finance provider (lender)?
Barclays Partner Finance will send a loan agreement pack approximately four weeks after delivery of the goods, confirming that the account has been activated and, from this point, it is possible to make repayments against the loan.
For further information on how our finance product work, see our Finance help section.
To apply for finance, follow these three easy steps
1. Add items to your basket, and click 'Checkout'.
2. When selecting your Payment Option, choose ‘Apply for Finance’, and select your offer and terms.
3. Complete the Barclays Online Application form.† Make sure you have your bank details at hand.
† Once your application has been accepted, usually within minutes, we will immediately dispatch your equipment.